t Master’s Thesis in Subjec T.G.A.L. Weerathunga February 2014

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Sustainable energy engineering master program

Examiner: Prof. Andrew Martin

Supervisor: Dr. Catharina Erlich

FACULTY OF ENGINEERING AND SUSTAINABLE DEVELOPMENT

ANALYSIS FOR AN ECONOMICALLY SUITABLE COAL TO PUTTALAM COAL

POWER STATION TO RUN THE PLANT IN FULL LOAD CAPACITY

T.G.A.L. Weerathunga

February 2014

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ABSTRACT

Sri Lanka is an island at the Indian Ocean with 65234 km2_{and it has a power demand of}

2000 MW. The hydro power was the main power source before year 2000, after maximum usage of hydro power Sri Lanka installed fossil fuel power plant to achieve the demand. Then the electricity price gradually increased due to higher increment of fuel price. As the solution for this higher price of electricity the government has to go to new profitable power source the coal power. Finally year 2011 Puttalam coal power plant 300 MW x 1 was installed with the hope of providing the low cost reliable energy supply to Sri Lanka and it will be extended to 300MW x 3 plan in year 2015. Therefore the puttalam coal power plant is the key power plant to the Sri Lankan power generation and it is expected to have the maximum output (base load) to the Power demand of Sri Lanka.

Sri Lanka is a tropical country and it has two different weather seasons as rainy season and dry season. The puttalam power plant situated at Kalpitiya peninsula and it has normally dry weather condition, Months of April, October November and December have heavy rain condition (Meteorological Department, Sri Lanka, 2012). The puttalam coal power plant may not achieve full load because of high moisture content at rainy season. So this Thesis carried out to find the capability to achieve the full load with available plant, plant capacity by using different coal qualities. Then find the economical benefits and effect on the environment with the recommended coal for different seasons and also design a storage plan to coal storage at existing coal yard.

Based on the historical data and the Meteorological department rain fall data and by doing a technical analysis the recommended coal type was selected and the capability of plant equipment capacity to the recommended coal to achieve the full load was analyzed. Then the coal storage plan was designed according to annual requirement of the different recommended coal and economical benefit was analyzed by considering last year cost for generated power and the generation cost, if recommended coal is used for last year. Finally flue gas analysis was carried out for the recommended coal to find the effect on the environment.

The recommended coal for rainy season is with the heating value of 6600 kcal/kg and for dry season it is 6300 kcal/kg. The capacities of main boiler and other plant equipments are capable for the recommended coal to achieve the full load of the plant. Then the design of the coal storage plan was given under figure 4.2 and table 4.1. It was calculated that a profit of 3.932 million US$ can be achieved by using the recommended coal for the last year and also when compared with the changing price of oil and coal it will be more profitable for the future. Because the oil price increases very rapidly and the increase in coal price is very low compared to the oil price. Finally the SOx and NOx emissions from

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ACKNOWLEDGMENT

I would like to convey my sincere appreciation to local supervisor Ms. L.U. Bakmeedeniya, kth supervisors Dr. Anders D Nordstrand and Dr. Catharina Erlich, who has the attitude and substance of brilliance; they constantly and persuasively conveyed a spirit of adventure in regard to master thesis, and enthusiasm in regard to instruction. Without their persistent guidance and help this thesis would not have been possible.

I would like to thank Mr. Ruchira Abeyweera who is the local coordinator of M. Sc in Sustainable Energy Engineering to his great coordination with Royal Institute of Technology. And also I convey my appreciation to Mr. B.P.G. Jayasignhe for advice and commitments on presentation skills.

Then I would like to extend my thanks to Professor Andrew Martin for his sense of understanding, supervision and the guidance given in completing the task.

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INDEX OF TABLES

Table 2.1: Weekly Average Power Generation and Coal Consumption data-……….. 10

Table 2.2: Weekly average rain fall data from January 2011 to April 2012………... 11

Table 2.3: Average rain fall data for 30 years………. 11

Table 2.4: Analyzed data of received coal………..….…… 12

Table 2.5: Coal price for the received coal………..……… 12

Table 3.1: Comparison of coal data, rain fall data, moisture contain……….. 14

Table 3.2: Coal flow rate at rain fall data at rain season………...……… 15

Table 3.3: Coal flow rate at Dry season………... 16

Table 3.4: Coal Specification……….. 19

Table 3.5: Coal conveying System……….. 24

Table 3.6: Capacity of the conveyer belts……… 24

Table 3.7: Main characteristics of stacker Re-claimer………... 25

Table 3.8: Roller screen capacity………..……… 26

Table 3.9: Ring hammer capacity………. 27

Table 4.1: Result of coal yard design from trial and error method………... 31

Table 5.1: Average coal price for selected rainy season coal………. 32

Table 5.2: Average coal price for selected dry season coal……….…………...……… 32

Table 5.3: Total coal cost and total units for rainy season……….. 34

Table 5.4: Total coal cost and total units for dry season………...……… 34

Table 5.5: The economical benefit after using the recommended coal (Duration may 2011 to march 2012)………..………….. 36

Table 6.1: Components at recommended coal……….………. 37

Table 6.2: Summary of environmental analysis……….……… 40

Table 7.1: Selected coal for Rainy and dry seasons……….……… 41

Table 7.2: Compatibility with Coal Pulverizes……….……… 41

Table 7.3: Coal unloading time……….. 41

Table 7.4: Coal Conveying System………... 41

Table 7.5: Design a storage plan by using exiting coal yard……… 42

Table 7.6: The economical benefit after using the recommended coal (Duration may 2011 to march 2012)……… 42

Table 7.7: Summary of environmental analysis……….. 42

Table 8.1: Electricity plan of Sri Lanka……… 43

Table 8.2: Capacities and Average unit cost of thermal power plant………. 44

INDEX OF FIGURES

Figure 1.1: location of the plant………... 01

Figure 1.2: Schematic diagram of Puttalam Coal power station Phase I………. 02

Figure 1.3: An illustration of the coal mill……….……….. 03

Figure 1.4: Schematic diagram for implemented coal power plant with cooling tower……..…… 04

Figure 1.5: Schematic diagram of Continuous Flow Fluidized Bed Coal Dryer……….…….. 04

Figure 1.6: Schematic diagram of fluidized bed dryer……….……… 05

Figure 1.7: Specified mill running condition……….. 06

Figure 2.1: Load Curve of Sri Lanka………... 09

Figure 3.1: Coal Unloader………... 21

Figure 3.2: Coal handling system……… 23

Figure 4.1: Coal storage file……….……… 29

Figure 4.2: Plan layout of designed coal yard……… 31

Figure 8.1: Average price paid by UK power producers for coal, oil and natural gas 1999 to 2011………. 44

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INDEX OF GRAPH

Graph 3.1: GCV vs Power at rainy season……….. 15

Graph 3.2: GCV vs Power at Dry season………. 17

TABLE OF APPENDIX

Appendix 1: Coal Consumption of Puttalam Coal Power Station………..……….. 49~ 55 Appendix 2: Combustion table for dry season coal………...……… 56

Appendix 3: Combustion table for rainy season coal………...………. 57

Appendix 4.1: Cost of received coal to Puttalam Coal Power Plant…………...……… 58

Appendix 4.2: Cost of received coal to Puttalam Coal Power Plant………,,,……… 58

NOMENCLATURE

Nomenclature Unit Description

B m Belt width

BMCR MW Boiler Maximum Continuous Rating

ESP - Electro Static Preceptor

FGD - Flue Gas Desulfurization

F.T. oC Fluid Temperature

GCV kcal/kg Gross Calorific value

H hour Hour

HGI - Hardness Grove Index

IDT o

C Initial Deformation Temperature

L m Length of stock pile

M kg Mass

N rpm Rotating speed

PCPP - Puttlam Coal Power Plant

P, Q m2 _{Dry season coal storage area}

R, S m2 Rainy season coal storage area

Rs - Sri Lankan Rupees

T ton Ton

Φ m Idler diameter

V m3 Volume of stock pile

Ρ kg/m2 Density

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1 INTRODUCTION

1.1 INTRODUCTION ON PUTTALAM COAL POWER PLANT

Sri Lanka is an island situated between the latitudes 6o 54’ north and longitudes 79o_{54’ east (http://wiki.answers.com, March 21, 2012). The}

country’s power requirement is met from hydro, diesel and oil fired steam and gas turbine power plants. Over the last few decades, Sri Lanka has exploited the existing hydro power energy resource potential to its maximum. According to present predictions the global oil and gas reserves are not expected to last beyond the next 85 years (Sousa, 2013) and it will not be economical to extract the remaining reserves. But in contrast, the global coal reserves are expected to last for the next 500 to 600 years. At present Sri Lanka is heavily depending on the electricity generated by thermal means and for next fifteen years the only fuel option for thermal generation has with regard to base load operation is coal. Therefore due to the scarcity of the fossil fuels and the increasing demand on electricity the country’s electrical generating capacity could best be met by constructing thermal power plants based on coal.

The Puttalam Coal Power Plant which is the concern of this project is to develop 900 MW (electrical output) coal-fired base load steam power plant. The Power Plant is located on the north-west coast of Sri Lanka which is about 12 km west of Puttalam town, the capital of Puttalam district in the Kalpitiya peninsula (Google map, 2010). The geographical co-ordinates are approximately 80 02’ latitude north and 790 43’ longitudes east (www.distancesfrom.com). The power plant area gets an annual rainfall about 1000 mm mostly due to monsoon (Meteorological Department, Sri Lanka, 2012).

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The full capacity of the plant has design to complete in 2 phases. The first phase comprises the installation of a unit with a net capacity of 300 MW (electrical output) with 85% plant factor, providing around 2,122 GWh of energy per annum; the construction of a transmission line; and the construction of a jetty that extends seawards for about 700m to the minus 15 m bathymetric contour (Technical Document of PCPP, 2006).

The jetty is equipped with a conveyor belt, which carries coal, off-loaded from ships, to the plant site. Construction of the first phase was completed in late year 2010 and commissioned in early year 2011.

The plant will be upgraded to 900MW (electrical output) in the second phase by adding another 2 number of 300MW units and the construction has started in year 2011 expecting to be commissioned in year 2014. Thus at full completion, the plant will comprise 3 electrical generating units, each having a maximum capacity of 300 MW (Technical Document of PCPP, 2006).

Figure 1.2: Schematic diagram of Puttalam Coal power station Phase I

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3 1.2 LITERATURE SURVEY

The main fuel of coal fire power plant is coal and it consist of various components as Carbon, Sulpher, ash, volatile matter, moisture and that the coal is categorized based on above composition as Bituman, sub-Batumi, and lignite coal. The moisture content is highly affecting to the coal quality and it is one of the main facts which change the plant performance directly. High moisture content of coal reduce the mill performance as well as furnace performance then uncompleted burning of coal can happen inside the furnace and it is seriously affecting to the environment through stack emissions, then the plant maintance will be a crucial event, instead of that coal handling problems also take place(Odgaard et. al, 2007).

There are different types of methods to reduce the moisture content at the coal as below,

 Preventing performance of coal mill from the high moisture content of coal

The coal powder blow in to the furnace by conveying with mixture of hot and cold primary air. The coal mills are used to grind the large particles in to powder form. The coal mill inside consist of a number of rollers to pulverized the coal. This pulverized coal convey to the boiler furnace by hot and cold air mixture. The mixed primary air used for two different processes. One is to evaporate the moisture and dry out the pulverized coal and another one is to separate the qualified fine coal dust (more than 75% passes through 200 mesh BIS sieve is the qualified pulverized coal) then convey it in to furnace. The method is to remove the moisture by heating up the pulverized coal up to 100oC, and then the moisture evaporates form the pulverized coal (Odgaard et. al, 2007)

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 Method of removing moisture from coal before the pulverizer

It is considered as using the waste heat of power plant to reduce coal moisture before pulverizing the coal, and then the result will be improved operations, reduced emissions, and reduced makeup water used for evaporative cooling.

Figure 1.4: Schematic diagram for implemented coal power plant with cooling tower (Lehigh energy update, 2006)

Some positive and negative effects can be found for coal drying before pulverizing. When coal has less moisture (dry coal) mill power and power need to secondary air by using forced draft fans and induced draft fans both deceased, while additional power is required to fluidization air of the fluidized bed coal dryer.

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The Puttalam coal power plant has sea water cooling system, Instead of having cooling tower. So waste heat from condenser can be used as thermal energy to dryer and from this system it can decrease the moisture level about 20% in coal (Lehigh energy update, 2006)

 Method to remove the moisture is bubbling fluidized bed.

The fluidized bed used to store the pulverized coal before admit to the furnace. This pulverized coal may have moisture at the pulverized bed. So this method belongs to remove moisture from the bed by using waste heat at the condenser as below,

Figure 1.6: Schematic diagram of fluidized bed dryer (Edward et. al,

2006).

In this case waste heat used as steam to heat up the pulverized coal and air blow from bottom to the top of the fluidized bed to mix the coal powder to transfer the heat properly and remove the moisture (Edward et. al, 2006).

Steam in Steam out

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6 1.3 MOTIVATION

1 x 300 MW unit which installed under phase 1 is started for commercial power generation in April 2011 with the hope of providing the low cost reliable energy supply to Sri Lanka (Log book PCPP, 2011). As per the agreements with contractor; boilers, turbines, generators, Electro Static Preceptor (ESP) units, Flue Gas Desulfurization (FGD) units which designed for phase 2 are identical to phase 1 units and the entire 3 x 300 MW plant has design to run with same design coal (Technical Document of PCPP, 2006).

However 300 MW plant is unable to run in full capacity load all the time throughout the year due to following reasons,

1) Increased moisture content in coal during rainy seasons and at that time specified coal mill capacities are not enough to run the plant in 300MW.

2) Variations in the calorific value of the coal from the design valve. 3) Fixed running conditions of the mill as shown below.

Figure 1.7: Specified mill running conditions (Deputy General Manager

PCPP, 2011)

The Ceylon Electricity board loses huge amount of money due to above reasons apart from other unforeseen factors.

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Mix Coal Temperature < 70⁰C

Mix Air Temperature < 190⁰C

Coal Flow Rate < 30T/H

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7 1.4 OBJECTIVE

In this project it is expected to analyze how the quality of coal affects the electricity generation in different seasons of the year and then quantifying of financial benefits to the Ceylon Electricity Board while extending towards the technical and environmental analysis.

Scope

 The very first task of this project is to collect Data 1) Collect actual capacity data of plant equipments.

2) Collect weather data (rainy season, dry season and windy season) 3) Collect coal properties in Indonesian coal

 The second task is the technical analysis of the existing 300 MW plant for suitable coal for generating 300 MW throughout the year. The utmost focus is to identify the components and units in the critical path which modifications are needed.

 The third task is to design a storage plan by using the existing coal yard.

 The fourth task is to analyze the economical benefits after using selected coal according to the above technical analysis.

 The fifth task is to identify and predict the possible environmental issues which may rise with the feeding of different type of coal instead of designed coal to the existing plant and possible mitigations for those issues.

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2 METHODOLOGY

Necessary data for the analysis were obtained accordingly,

 Plant data – From the plant records

 Weather data – Meteorological department  Coal data – coal testing agent…etc

For technical analysis, properties of coal types, machinery specifications were exploited thoroughly. For this task the test reports from coal testing agent SGS Lanka (Pvt) Ltd and manufacturer design manuals, current capacities of plant equipments, weather report from meteorological department and plant drawings were taken in to consideration.

Planning of Stock fill for the existing coal yard according to seasonal coal requirement was done using coal properties and coal yard drawings by using mathematical calculation.

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9 2.1 DATA COLECTON

2.1.1 Collect actual capacity data of plant equipments

Coal consumption is the main data which was taken from the history of Puttalam Coal Power Station. One set of data was noted by considering the peak load during the day according to the Load curve of the Sri Lanka.

Figure 2.1: Load Curve of Sri Lanka (CEB system control center, 2012)

The maximum power demand of Sri Lanka is about 2000 MW (Annual report CEB, 2011) and it is between 17.00 hour to 21.00 hour. According to CEB rules and regulation Coal Power station can supply 25% of load from the demand. Therefore 20.00 hour is considered as the best time for data collection. Following data were taken at 20.00 hour (refer appendix 01).

1) Supply Load (MW)

2) Main Steam Pressure (MPa) 3) Coal Consumption (T/H) 4) Main Steam Temperature (0C) 0 500 1000 1500 2000 2500 0:3 0 1:3 0 2:3 0 3:3 0 4:3 0 5:3 0 6:3 0 7:3 0 8:3 0 9:3 0 10 :3 0 11 :3 0 12 :3 0 13 :3 0 14 :3 0 15 :3 0 16 :3 0 17 :3 0 18 :3 0 19 :3 0 20 :3 0 21 :3 0 22 :3 0 23 :3 0 MW Hour Daily Load Curve 2012-03-08

Mahaweli MW Laxapana MW Other Hydro MW Northern MW

Kelanitissa MW Private Power MW Sapugaskanda MW PCPP

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Table 2.1: Weekly Average Power Generation and Coal Consumption data (Control room PCPP, 2011, 2012)

Note; following details were considered for the calculation of average generated power and average coal consumption.

 Plant able to run in full load capacity without partial brake down.  System control center of CEB should request 300MW from the plant. Year Month Week

Average Power

(MW)

Average Coal Consumption

(T/H) Year Month Week

Average Power (MW) Average Coal Consumption (T/H) 2011 May 1 280 106.2 2011 November 1 290 109.4 2 286 110.7 2 N/A N/A 3 N/A N/A 3 293 104.9 4 N/A N/A 4 293 105.7 2011 June 1 300 109.0 2011 December 1 285 103.8

2 N/A N/A 2 N/A N/A

3 N/A N/A 3 N/A N/A

4 N/A N/A 4 N/A N/A

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11 2.1.2 Rain fall data of Puttalam District

Table 2.2: Weekly average rain fall data from January 2011 to April 2012

(Meteorological Department, Sri Lanka, 2011 and 2012)

Year Month Rain fall /(mm) 1st Week 2 nd Week 3 rd Week 4 th Week 2011 January 8.5 36.6 1.2 37.7 2011 February 56.4 1.1 28.9 18.1 2011 March 3 8.9 0 0 2011 April 0 37.9 22.3 110.9 2011 May 1.3 0 0.1 0.5 2011 June 7 5.6 0 0 2011 July 0 0 23.5 0 2011 August 5 0 0.2 0 2011 September 0 1.9 2.8 0 2011 October 0 0.7 43 135.6 2011 November 19.8 0.3 74.1 73.1 2011 December 0 14.5 26.1 19.6 2012 January 159.1 151.6 136.3 205.5 2012 February 34.9 22.8 0.4 31.5 2012 March 0 11.8 34.7 30.5 2012 April 0 46.9 31.6 22.3

Table 2.3: Average rain fall data for 30 years (Meteorological Department,

Sri Lanka)

Month 30 years average rainfall _data/(mm)

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2.1.3 Quality of received coal for Puttalam Coal Power Station

SGS Lanka (PVT) Ltd is the independent party who analyzes the received coal to the puttalam coal power station.

Table 2.4: Analyzed data of received coal

(Test report from SGS Lanka 2011, 2012)

Table 2.5: Coal price for the received coal (Finance department PCPP

2011, 2012)

Shipment GCV/(kcal/kg) _{cost/(US$/ton)}Unit

1 6373 159.68 2 6080 144.40 3 6116 149.79 4 6005 144.16 5 6236 155.08 6 6054 145.21 7 6658 184.23 8 6315 164.21 9 6649 187.54 10 6197 150.33 11 6195 151.22 12 6070 148.93 13 6161 148.65 14 6601 180.16

Date Shipment _(Kcal/Kg)GCV Ash _(%)

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3 TECHNICAL ANALYSIS

It can identify the coal flow rate of the coal mill is changed depend on moisture content of the coal, according to historical data. (Refer table 3.1 and 3.3) The weather condition directly affects the moisture content of coal, and then the amount of moisture directly affects the coal flow rate under the limitations of mill running parameters (Refer figure 1.3). Therefore coal flow rate of coal mill depends on the moisture content of the coal. The coal flow rate is depending as follow,

 If moisture content is high (at rainy season), the mixed air temperature is increased and it is limited to 190º C (other parameters of the figure 1.3 are within limits)

 Then in dry season, the mixed coal temperature is increased and limited to 70ºC(other other parameters of the figure 1.3 are within limits)

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Table 3.1: Comparison of coal data, rain fall data, moisture contain (Test

report from SGS Lanka, Control room PCPP, Laboratory report PCPP 2011, 2012)

According to moisture content it is divided in to two categories

1) Rain season-more than 14% moisture contain of coal (the rainfall is more than 70mm usually)

2) Dry season-less than 14% moisture contain of the coal Year Month Week Average Power

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3.1 CALCULATION OF COAL FLOW RATE AT RAINY SEASON Table 3.2: Coal flow rate at rain season

According to above table and figure coal which has a calorific value of 6658 kcal/kg with consumption rate of 104.8 T/H is suitable for rain season to generate 300MW.Therefore recommended coal for the rain season is of the calorific value 6600 kcal/kg with a consumption rate of 105 T/H.

240 250 260 270 280 290 300 310 6373 6236 6236 6236 6658 6658 6658 Pow er/( M W) GCV/(kcal/kg)

Graph 3.1: GCV vs Power at rainy season

Year Month Week Average Power

/ (MW) Average Coal consumption /(T/H) GCV /(kcal/kg) Rain fall /(mm) Moisture / (%) 2011 April 4 0 0 0 110.9 - 2011 _May 1 280 106.2 6373 1.3 15.57 2011 Oct. 4 261 100.1 6236 135.6 15.47 2011 Nov. 3 293 104.9 6236 74.1 14.89 2011 4 293 105.7 6236 73.1 15.14 2012 Jan. 1 296 106.6 6658 159.1 16.36 2 298 105.5 6658 151.6 17.17 3 298 105.0 6658 136.3 16.84

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3.2 CALCULATION OF COAL FLOW RATE AT DRY SEASON Table 3.3: Coal flow rate at Dry season

Year Month Week

Average Power /(MW) Average Coal consumption /(T/H) GCV /(kcal/kg) Rain fall /(mm) Moisture /(%) 2011 May 2 286 110.7 6373 0 12.24 2011 June 1 300 109.0 6373 7 8.02 2011 July 3 285 107.8 6080 23.5 11.28 4 282 107.1 6080 0 9.5 2011 Aug. 1 286 108.3 6080 5 9.42 2 300 108.7 6116 0 8.73 3 298 106.2 6116 0.2 8.21 4 286 107.7 6116 0 8.05 2011 Sept. 1 297 108.3 6116 0 7.49 2 290 106.9 6116 1.9 7.42 3 284 103.2 6080 2.8 8.46 2011 Nov. 1 290 109.4 6236 19.8 12.31 2011 Dec. 1 285 103.8 6236 0 12.75 2012 Feb. 3 299 108.3 6315 0.4 12.47 4 292 107.9 6315 31.5 12.87 2012 March 1 299 108.7 6315 0 11.94 2 299 108.5 6315 11.8 11.83 3 288 107.6 6315 34.7 12.86 4 283 106.9 6197 30.5 13.27 2012 April 1 291 107.2 6197 0 11.4 2 283 107.2 6197 46.9 12.63 3 285 107.1 6197 31.6 11.48 4 268 105.6 6054 22.3 10.52

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According to above table and figure, the calorific values of 6373 kcal/kg and 6315 kcal/kg coal with consumption rate of 107.5 T/H is suitable for dry season to generate 300 MW. Therefore recommended coal for the dry season is 6300 kcal/kg with consumption rate of 108 T/H.

250 260 270 280 290 300 310 63 73 63 73 60 80 60 80 60 80 61 16 61 16 61 16 61 16 61 16 60 80 62 36 62 36 63 15 63 15 63 15 63 15 63 15 61 97 61 97 61 97 61 97 60 54 Pow er/( M W) GCV/(kcal/kg)

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3.3 CALCULATION OF COMPATIBILITY OF EXISTING PLANT WITH RECOMMENDED COAL

3.3.1 Design Specifications of Coal for Puttalam Coal Power station Coal specification usually focuses on the properties of coal which would affect the complete functionality of a power plant and the use of technology to use in the design stage. There are two main basis of analysis. Proximate analysis -Indicates the percentage by weight of the Fixed Carbon, Volatiles, Ash, and Moisture Content in coal (Technical Document of PPCP, 2006).

Ultimate analysis -Determines all coal component elements, solid or gaseous

The ultimate analysis is done in a properly equipped laboratory by a skilled chemist, while proximate analysis can be done with a simple apparatus

The amounts of fixed carbon and volatile combustible matter directly contribute to the heating value of coal. Fixed carbon acts as a main heat generator during burning. High volatile matter content indicates easy ignition of fuel. The ash content is important in the design of the furnace grate, combustion volume, pollution control equipment and ash handling systems of a furnace (Technical Document of PPCP, 2006).

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Table 3.4: Coal Specification (Technical Document of PPCP, 2006).

The specification of recommended coal is compatible with above design specifications of coal for Puttalam coal power station. (Specially, the calorific value of the recommended coal is in the range of design specification and other parameters of the coal is in the design rang, refer table 2.4)

Guarantee Design Rainy

Season Range PROXIMATE (As Received) Total Moisture % 12.0 16.0 19.0 8.0-16.0 Volatile Matter % 27.0 25.0 24.9 21.9-39.9 Fixed Carbon % 49.5 43.3 45.5 41.3-57.1 Sulphur % 0.5 0.7 0.5 0.2 -0.7 Ash % 11.0 15.0 10.1 4.5 -16.0 Heating Value MJ/Kg 26.4 25.3 24.7 24.8 – 28.9 HHV kcal /kg 6,300.0 6,050.0 5,900.0 5,820 – 6,900

ULTIMATE (As Received)

Moisture % 12.0 16.0 19.0 8.0-16.0 Carbon % 65.0 60.0 60.5 61.4-68.7 Hydrogen % 3.8 3.6 3.4 3.4-4.3 Nitrogen % 1.5 1.7 1.4 1.0-1.6 Oxygen % 6.2 3.0 5.1 6.5-12.1 Sulphur % 0.5 0.7 0.5 0.2-0.7 Ash % 11.0 15.0 10.1 4.5-16.0

ASH (DRY BASIS)

SiO2 % 61.0 58.0 61.0 43.0-74.0 Al2O3 % 25.0 21.6 25.0 11.9-36.0 Fe2O3 % 4.0 8.0 4.0 0.4-17.4 CaO % 3.5 5.0 3.5 0.2-9.4 MgO % 0.7 0.5 0.7 0.2-6.2 Na2O % 0.3 1.2 0.3 0.1-1.5 K2O % 0.6 0.8 0.6 0.3-1.3 TiO2 % 1.3 1.3 1.3 1-1.6 P2O5 % 0.9 0.9 0.9 0.1-1.6 SO3 % 2.7 2.7 2.7 0.1-5.4

ASH FUSION TEMP (AS REDUCED)

IDT (Initial Deformation

Temperature) 0_C 1,250 1,170 1,250 1150-1300

F.T. (Fluid Temperature) 0_C _1,325 _1,300 _1,325 _1250-1500

HGI (Hardness Grove

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20 3.3.2 Compatibility with Main Boiler

Type: 300 MW Class Boiler, Natural circulation, re- heater, Drum Type, Sub-critical, Semi outdoor (roof and cladding in the upper boiler part) with standard technology.

 Fuel Type Bituminous Coal

 Heating Value 5800-6900 kcal/kg (24.5--28.9) MJ/kg  Draft Balance Balanced Draft

 Firing System Tangential corner firing, Tilting burners  Minimum stable Load 35% (BMCR)

(Technical Document of PPCP, 2006)

According to above analysis, the recommended heating values of coal can be selected as 6300 Kcal/kg, 6600Kcal/kg for dry and rainy seasons and complied with the boiler specification.

3.3.3 Compatibility with Coal Pulverizes

Design capacity of each coal mill is 8.73 kg/s. (design coal 6050 kcal/kg) 5 pulverizes (4 in operation, 1 stand-by), sized according the requirements of the coal and the Pulverizer boiler (Technical Document of PPCP, 2006).

Pulverizer will meet the quantity of "any specified" coal pulverized with a fineness of no less than 75 percent through 200 mm mesh when the unit is operating at maximum continuous output(Technical Document of PPCP, 2006).

Total design capacity of all 4 coal mills =8.73 x 4 x 3.6 T/H =125.71 T/H

However under current situation mill capacity limited to 108 T/H and also the coal feeder capacity is limited to 30 T/H(Centralized control operation regulation of PCPP, 2012c), it is not complied with design capacity and design coal feeder rate as follow,

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Design capacity of each coal feeder is 9.6 kg/s (design coal 6050 kcal/kg) Total design capacity of 4 coal feeders = 9.6 x 4 x 3.6 T/H

=138.24 T/H Actual total capacity of 4 coal feeders = 30 x 4 T/H

= 120 T/H

Above data are tankan from Technical document of the Puttalam coal power station.

According to above specifications of coal feeder and coal pulverizes maximum coal rate should be below 108 T/H. Therefore above recommended coal is capable of supplying 300 MW at rainy and dry seasons.

3.3.4 Compatibility with Coal Unloading

Figure 3.1: Coal Unloader (captured from PCPP, 2012)

Designed unloading capacity for entire power plant is 1500 T/H and installed capacity for phase I is 1000 T/H by using 2 units of 500 T/H unloading cranes which proved to work with 5000 T barges(Technical Document of PPCP, 2006). The function of the ship unloader is to transport the coal from the vessel to the belt conveyer system on the wharf. The 5000 T barges shall transport the coal to the wharf, while the grabbing bucket will grab the coal from the vessel and then unload in the hopper. Afterward the coal in the hopper is directed to the belt conveyor.

Even though the rated capacities for each of the unloaders are 2 x 500 T/H the working capacity is limited to a factor of nearly 0.7 due to various unavoidable reasons.

Hopper

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22

Unloading time required for each 5000 T barge can be calculated as follows, Time taken to take barge from jetty to vessel = 1 H

Time taken for Loading coal to the barge = 6 H Bringing back and berthing to jettey = 1.5 H

Time taken for Unloading the barge = 5000/ (1000 x 0.7) = 7.14 H

Total unloading time = (1+6+1.5+7.14) = 15.64 H

Actual unloading factor = 2

(This factor is introduced considering the ability to carry out the simultaneous operation of all these barge handling, loading and unloading operations) Average unloading rate = (5000 x 2)/ 15.64 T/H

= 639.38 T/H

Unloading time for recommended coal (6,300 kcal/kg) which consumes at a rate of 108 T/H for 300 MW units is calculated as follows

Total unloading time for required coal quantity = (108x24x365) / (639.38x24)

= 62 days

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23

3.3.5 Compatibility with Coal Conveying System

Compatibility with the Coal process path is evaluated as follows. 1. Conveyor belt system 2. Stacker re-claimer 3. Crusher house

Figure 3.2: Coal handling system (Capture from coal control room PCPP,

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24

Table 3.5: Coal conveying System (Technical Document of PPCP, 2006).

Conveying belts Descriptions

C0 The coal unloads from barge to conveyer C_{unloaders at the jetty.} 0 using coal

C6

It is directed coal from C0 conveyer belt to C6 conveyer

belt from Junction tower and it is changed feed direction of 90o_{.Stacker re-claimer has installed in C}

6 for stack to

coal yard and reclaimed coal from coal yard.

C5A, C5B Those belts are conveying coal from underground _{hoppers to belts C} 4A, C4B.

C4A, C4B

It is directed coal from C5A, C5B belts to C4A, C4B

conveyer belts from transfer tower 1 and it change feed direction of 90o_.

C3A, C3B

It is directed coal from C6, C4A, C4B belts to C3A, C3B belts

and then it convey to crusher house to crush the coal to small particle less than 30 mm size.

C2A, C2B The crushed coal conveys to C_C 1A, C1B belts through the 2A, C2B.

C1A, C2B It is directed coal to Coal bunker 1, 2,3,4,5 by using plow _unloaders.

Table 3.6: Capacity of the conveyer belts (Technical Document of PPCP,

2006). Belt Width (mm) Speed (m/s) Capacity(T/H) Length (m) Power (kw) C0 1200 3.15 1500 682.22 315 C1A, C1B 1000 2.0 600 56.735 45 C2A, C2B 1000 2.0 600 184.58 200 C3A, C3B 1000 2.0 600 395.85 185 C4A, C4B 1000 2.0 600 76.25 55 C5A, C5B 1000 2.0 600 121.25 110 C6 1400 2.5 1500 568.45 355

Bucket wheel Stacker re-claimer

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Table 3.7: Main characteristics of stacker Re-claimer (Technical

Document of PPCP, 2006).

Parameter Specification

Material characteristic Breed ： coal Bulk density： 0.85T/m3 Pellet size： ≤350mm Static bulk angle： 40°～ 45° Production Capacity Stacking：1500 T/H

Reclaimer：600 T/H stacking high Above rail：10.5 m

Below rail：1.5 m

Bucket-wheel mechanism Bucket-wheel style: no style

Bucket-wheel Diameter：φ5200mm No. of bucket-wheels ： 8

Bucket-wheel rotating speed： 6.7 r/min

Transmission form: Electric motor→ redactor →bucket-wheel shaft →bucket-wheel body Drive set construction: Integer suspended type

Boom belt convey Belt style: Reversible form of ordinary groove Belt width： B=1400mm

Belt speed： V=2.5m／s Idler diameter: Φ=133mm Motor: style：Y280s-4 Power: N=75 kW

Rotating speed: n=1480 r/min

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26 Crusher house operations.

The chrusher house consists of Rolling shaft screen and Ring hammer type coal crusher.

Rolling shaft screen (Technical Document of PPCP, 2006).

The crusher efficiency is improved by rolling shaft screen; it will be sieved with rolling shaft screen, before raw coal enters into coal crusher.10-shaft rolling shaft screen adopts multi-roll to screen the materials with a desired size and at the same time push larger materials to the coal crusher for further crushing.

Table 3.8: roller screen capacity (Technical Document of PPCP, 2006).

Description Unit Specification

Model Set HGS1210 type

Capacity T/H 600

Sieving efficiency - ≥95%

Width of screen face mm 1200 Number of screen shafts shaft 10 Grain size of under sieves mm ≤30

Ring hammer type coal crusher (Technical Document of PPCP, 2006).

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Table 3.9: Ring hammer capacity (Technical Document of PPCP, 2006).

Description Unit specification

Model set HCSZ-500 type

Capacity t/h 500

Grain size of feeding material mm _≤350

Grain size of discharging material mm ≤30 Model of motor set YKK400-8

Voltage kV 6

Rotating speed r/min 743

Power kW 220

The 1st unit have 5 numbers of bunkers and 1 bunker were kept stand by which has a rated capacity of 200 tons each and for calculations the standby bunkers were not considered.

Capacity of a bunker = 200 T

Consumption rate from 1 mill = 108/4 T/H = 27 T/H Consumption time at rated load = 200 / 27

= 7.40 H Time left for next feeding = 6.40 H (1 hr safety factor considered)

Belt capacity required to support the rated load = (5-1) x 200/ 6.40

= 125 T/H

The Bucket wheel re-claimer capacity is 600 T/H, the roller screen capacity is 600 T/H and the ring hammer capacity is 500 T/H. But the required coal rate to support the rated load is 125 T/H. The each belt capacity which is used to supply coal to bunkers is 600 T/H, so it is more than required coal rate to support the rated load. The unloading rate from Jetty is 1000 T/H but the belts (C6 and C0) capacity for unloading is 1500 T/H and bucket wheel Stacking

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4 DESIGN A STORAGE PLAN BY USING EXISTING COAL

YARD

There are two season as rainy season and dry season and durations of those seasons are considered according to Average rain fall data for 30 years (Refer table 2.3).

Rainy season is considered as more than 100 mm rain from average rain fall for 30 years.

Accordingly, April, October, November, December is the rainy season and except of these months it is considered as dry season.

Duration of rainy season = (30+31+30+31) days

= 122 days

= 2928 H

Coal consumption (6600 kcal/kg) = 105 T/H Required coal for rain season = 2928 x 105 T

= 307,440 T

Duration of dry season = (365-122) days

= 5832 H

Coal consumption (6300 kcal/kg) = 108 T/H Required coal for dry season = 5832 x 108 T

= 629,856 T

The coal yard has a design storage capacity of 425,000 ton(Technical Document of PPCP, 2006), which meet up with the coal consumption for 155 days and there is a dry coal shed with capacity of 19,152 ton, it meets up with the coal consumption for 7 days(Technical Document of PPCP, 2006). The dry coal shed is used for rainy season to keep coal in dry condition which is fed to the coal mill.

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29 At monsoon season,

No of days in rainy season = 30+31 days = 61 days

Required recomended coal = 61 x 24 x 105 T = 153,720 T No of days in dry season = 30+31 days

= 61 days

Required recommended coal = 61 x 24 x 108 T = 158,112 T

Total required coal for monsoon season = 153,720+158,112 T = 311,832 T

Excess coal yard capacity = 425,000-311,832 T = 113,168 T

Recommended coal requirement may desired according to above calculation and coal yard capacity as follow,

Selected coal for rainy season = 180,000 T Selected coal for dry season = 245,000 T

Figure 4.1; Coal stoke fill in coal yard

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30 L = H = 12 m

A1 = A – 2L

Ba1 = Ba – 2L

V = H/6 [(2A+A1) Ba + (2A1+A) Ba1]

M = ρ V

M = ρ H/6[(2A+A1) Ba + (2A1+A) Ba1]……… (1)

ρ = 900 kg/m3

Calculation of coal storage,

P, Q sides used to store the dry season coal and R, S sides use to store the rain season coal (Refer figure 4.2)

Equation (1) can simplify as follow,

M = 1.8 [ (3A-24) Ba+(3A-48) (Ba-24) ]……….. (2)

It can find the best storage plan for coal yard by using above (2) equation from trial and error method.

There is fixed valve for A (for above equation 2) as below, Width of sea side (Ba for P & R sides) = 45 m Width of Land side (Ba for Q & S sides) = 120 m

The total length of the coal yard is 300 m (Technical Document of PPCP, 2006) and part of that length consider as variable Ba then using trial and error method fund that appropriate Ba values as follow.

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Table 4.1: Result of coal yard design from trial and error method

Figure 4.2: Plan layout of designed coal yard

Length /(m)

Coal for dry season

Coal for rainy

season _{Coal for}

dry season /(T) Coal for rainy season /(T) Total storage coal /(T) P

side/(T) side/(T) Q side/(T) R side/(T)S P side Q side R side S side 150 150 150 150 49,702 161,482 49,702 161,482 211,183 211,183 422,366 160 160 140 140 53,266 173,146 46,138 149,818 226,411 195,955 422,366 170 170 130 130 56,830 184,810 42,574 138,154 241,639 180,727 422,366 180 180 120 120 60,394 196,474 39,010 126,490 256,867 165,499 422,366 170 m 120 m 45 m 130 m

A B

C D

No.01

Coal conveying Belt

Sea side _P Land side

Q

R _S

C6

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5 ANALYSIS OF THE ECONOMICAL BENEFIT AFTER USING

THE RECOMMENDED COAL

In the economical analysis only the coal cost is considered. Because of it, the major cost component for the power generation, in addition to water consumption, auxiliary power consumption and depreciation of plant equipment should be added to the cost analysis but it is comparatively less amount when generated powers vary between 275 MW and 300 MW.

The coal cost for selected coals are considered as average price from received coal (refer table 2.5).

Following shipments are considered for the cost of selected rainy season coal which has 6600 kcal/kg (GCV),

Table 5.1: Average coal price for selected rainy season coal

Shipment GCV/(kcal/kg) Unit

cost/(US$/T)

7 6658 184.23

9 6649 187.54

14 6601 180.16

Average cost 183.98

Following shipments are considered for the cost of selected dry season coal which has 6300 kcal/kg (GCV),

Table 5.2: Average coal price for selected dry season coal

Shipment GCV/(kcal/kg) Unit

cost/(US$/T)

1 6373 159.68 9 6315 164.21

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33 Rainy season

Consider data set of 2011 May, 1st week (refer table 3.2) for calculation of coal cost and generated units from consumed coal,

Generated average power = 280 MW Average coal consumption = 106.2 T/H

Coal cost = 159.68 $/T

Assume 280 MW power generated through 24 H over7 days

Total Coal cost for generated power = 106.2×24×7×159.68 $

= 2,848,946 $

= 2.849 million $

Total generated units = 280×24×7×103 kWH

= 47, 040,000 kWH

= 47.04 GWH

If recommended coal is used for rainy season of 2011 May, 1st week

Selected coal = 6600 kcal/kg

Average power could be generated = 300 MW Average coal consumption = 105 T/H

Coal cost = 183.98 $

Assume 300 MW power can generate through over the 24 H and 7 days Total coal cost to generate the power = 105×24×7×183.98 $

= 3,245,407 $

= 3.245 million $

Total units could be generated = 300×24×7×103 kWH

= 50,400,000 kWH

= 50.40 GWH

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Table 5.3: Total coal cost and total units for rainy season

Consumed Coal Selected Coal

Year Month Week Average Power /(MW) Average Coal Consum. GCV /(kcal/kg) Coal cost /($/T) Total coal cost for generated power /(million $) Produced units /(GWH) Total coal cost for generate power /(million $) Units can produce /(GWH) 2011 April 4 - - - - - - May 1 280 106.2 6373 159.68 2.849 47.040 3.245 50.40 Oct. 4 261 100.1 6236 155.08 2.608 43.881 3.245 50.40 Nov. 3 293 104.9 6236 155.08 2.733 49.156 3.245 50.40 4 293 105.7 6236 155.08 2.754 49.196 3.245 50.40 2012 Jan. 1 296 106.6 6658 184.23 3.298 49.728 3.245 50.40 2 298 105.5 6658 184.23 3.264 49.980 3.245 50.40 3 298 105.0 6658 184.23 3.249 50.120 3.245 50.40 Total 20.755 339.102 22.718 352.80

Table 5.4: Total coal cost and total units for dry season

Consumed Coal Selected Coal

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Therefore the additional coal cost = (90.302) - (84.399) for generation of 300 MW

= 5,903 million $

Additional units that can be produced, = (1,512.000 -1,456.684) If recommended coal is used

= 55.316 GWH Cost for purchase additional unit = 23.47 LKR

(CEB should purchase power from Independent Power Producers (IPP), the average unit price is 23.47 LKR (System control, CEB) and exchange rate is 132 US$)

The cost for purchase additional units = 55.316 x 23.47 / 132

= 9.835 million $

Therefore if recommended coal is used, = 9.835 – 5.903 Economical benefit for CEB (profit)

= 3.932 million $

Total coal cost for generated power from

may,2011 to march,2012 =

Cost for rainy season +

Cost for dry season

Total generated units = _{rainy season}Units for + _{dry season}Units for

Total coal cost for generate power from may,2011 to march,2012

= _{rainy season +}Cost for _{dry season}Cost for

Total units can

generate = rain seasonUnits for +

Units for dry season = (20.755) + (63.644) = 84.399 million $ = (339.102) + (1,117.582) = 1,456.684 GWH

If recommended coal is used,

= (22.718) + (67.584) = 90.302 million $

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Table 5.5: The economical benefit after using the recommended coal (duration may 2011 to march 2012)

Descriptions Consumed _coal

If

recommended

coal is used Unit

power generation 1,456.685 1,512.000 GWH Generation cost 84.399 90.302 Million _$ Additional unit can generate from

recommended coal 55.315 GWH

coal cost for that additional units 5.903 Million _$ The cost, if CEB perches this

additional unit from IPP 9.835

Million $ Profit for CEB, if recommended

coal is used 3.932

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6 Environmental Analysis

Average Coal composition on wet Basis (mass %) for recommended coal is given below

Following data were assumed according to the boiler specifications (Centralized control operation regulation of PCPP, 2012c).

Flue gas temperature (Before the FGD unit) 1300C Air factor for combustion 1.25 Coal flow for rainy season 105 T/H Coal flow for dry season 108 T/H Density of SO2 at normal condition 2.9214 kg/mn3

Density of CO2 at normal condition 1.9783 kg/mn3

Components

Recommended coal for rainy season, 6600

kcal/kg/ (%)

Recommended coal for dry season, 6300 kcal/kg/ (%) C 69.6 62.9 H2 4.76 5.45 N2 1.27 1.25 O2 6.8 7.14 S 0.74 0.82 Ash 11.5 15.15 Moisture 5.33 7.29 Total 100 100

Table 6.1: Components at recommended coal

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Properties analysis of flue gas for rainy season

(Combustion table for above coal composition is shown in Appendix 03)  Flue gas flow = { total gas x fuel flow rate x (273+130)}/273

= {9.45 x 105000 x (273+130)}/273 = 1464750 m3/H

{From combustion table-Flue gas flow is 9.45 mn3/kg of fuel}

 The fraction of SO2 = SO2/Flue Gas

in total flue gas(Before FGD)

= 0 .231 x 106/421.81 = 547.64 ppm

in total flue gas(After FGD)

=0.231 x .05 x 106/421.81

=27.382 ppm (assumed the flue gas amount does not change)

{From combustion table-SO2 in flue gas 0.231 mol/kg of fuel, Total Flue

gas 421.81 mol/kg of Fuel}

 SO2 emission = SO2 Flow(mn3/kg of fuel) x Fuel flow x Density

(before FGD) = 0.231x0.0224x105x2.9214 T/H = 1.587 T/H

(after FGD) = 0.231x 0.05x0.0224x105x2.9214 T/H = 0.079 T/H

 CO2 emission = CO2 Flow(mn3/kg of fuel) x Fuel flow x Density

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Properties analysis of flue gas for dry season

(Combustion table for above coal composition is shown in Appendix 02)  Flue gas flow = { total gas x fuel flow rate x (273+130)}/273

= {8.99 x 108000 x (273+130)}/273 = 1433262 m3/H

{From combustion table-Flue gas flow is 8.99 mn3/kg of fuel}

in total flue gas(before FGD)

= 0 .256 x 106/401.14 = 638.18 ppm

in total flue gas(after FGD)

= 0 .256 x 0.05 x 106/421.81

= 28.73 ppm(assumed the flue gas amount does not change)

{From combustion table-SO2 in flue gas 0.256 mol/kg of fuel, Total Flue

gas 401.14 mol/kg of Fuel}

(before FGD) = 0.256 x 0.0224 x 108x2.9214 T/H = 1.809 T/H

(after FGD) = 0.256 x .05 x 0.0224 x 108x2.9214 T/H = 0.090 T/H

 CO2 emission = CO2 Flow(mn3/kg of fuel) x Fuel flow x Density

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Seawater desulphurization system is provided to remove 95% SO2 from flue

gas (Technical Document of PPCP, 2006).

Low NOX burner is provided to reduce the NOX emission rate, the limitation

for emission of NOX, according to contract document is 200 ppm (Technical

Document of PPCP, 2006) and according to environment authority it is 415 ppm. But the NO production rate of this power plant less than 130 ppm (Average NOX emission value taken from Environmental Engineer,

Environmental Department, Puttalam Coal Power Plant)

High efficiency Electro Static Precipitator (ESP) is equipped to lower the concentration of dust at the outlet of ESP (Dust removal efficiency no less than 99.5 % (Technical Document of PPCP, 2006)).

By taking the above measures, it is calculated that the emit concentration of SO2 ,Concentration of CO2 ,SO2 fractions as follow and it is meet the

environmental requirements.

Table 6.2: Summary of environmental analysis

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7 RESULTS

Table 7.1: Selected coal for Rainy and dry seasons

Season Selected coal/(kcal/kg) Calculated Coal consumption(T/H) Selected Coal consumption /(T/H) Rainy season 6600 104.8 105 Dry season 6300 107.5 108

Table 7.2: Compatibility with Coal Pulverizes

Descriptions Coal flow rate

/ (T/H) Design capacity

from 4 mills 126.7 Design capacity

from 4 feeders 136 Actual capacity from

4 feeders 120

maximum coal flow rate for recommended coal

108

Table 7.3: Coal unloading time

Unloading Time Days

Available unloading time 196

Required unloading time 62

Table 7.4: Coal Conveying System

Conveying system Coal flow rate /(T/H)

Belt capacity Coal convey

to crusher 600

Reclaim capacity of

reclaimer 600

Ring hammer capacity 500 Roller screen capacity 600 Required coal supply rate

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Table 7.5: Design a storage plan by using exiting coal yard

Table 7.6: The economical benefit after using the recommended coal (duration may 2011 to march 2012)

Table 7.7: Summary of environmental analysis

Emissions Rainy season Dry season

Concentration of SO2/(T/H),Before FGD 1.587 1.809 Concentration of SO2/(T/H),After FGD 0.079 0.090 SO2 fraction/(ppm), Before FGD 547.64 638.18 SO2 fraction/(ppm), After FGD 27.38 28.73 Concentration of CO2/(T/H) 262.8 244.3

Storage plan Coal storage/(T)

Total coal requirement for rainy season 307,440 Total coal requirement for dry season 629,856 Required coal for rainy season at monsoon time 153,720 Required coal for dry season at monsoon time 158,112 Design coal storage capacity for rainy season 180,727 Design coal storage capacity for dry season 241,639

Descriptions Consumed _coal If recommended _{coal is used} Unit

power generation 1,456.685 1,512.000 GWH Generation cost 84.399 90.302 Million _$ Additional unit can generate from

recommended coal 55.315 GWH

coal cost for that additional units 5.903 Million _$ The cost, if CEB perches this

additional unit from IPP 9.835

Million $ Profit for CEB, if recommended

coal is used 3.932

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8 DISCUSSIONS AND CONCLUSIONS

Sri Lanka is a developing country in South Asia with maximum GDP growth rate of 8.3 GDP (http://www.tradingeconomics.com/sri-lanka/gdp-growth,2013.5.13).The industries are developing very rapidly and new construction going on all over the country like Maththala air port, Hambanthota Harbor, Colombo city development project, Road development with high ways, Coal power project at Norochcholei and Sampoor etc. The electricity demand is highly increased with those developments. The current electricity demand at the peak time is about 2000 MW and to achieve that demand Sri Lanka has different kind of load sources, they are

(http://en.wikipedia.org/wiki/Electricity_in_Sri_Lanka), 1) Hydro Power - 1401MW 2) Thermal Power - 1690 MW Petroleum Power - 1390 MW Coal Power - 300 MW 3) Other

(Wind Power, Solar power) - 50 MW

The Ceylon Electricity Board (CEB) is the main electricity power producer, the electricity demand increase rapidly with development of the country, therefore Sri Lanka has electricity generation plan as below,

Table 8.1: Electricity plan of Sri Lanka (Generation plan of CEB, 2012)

Power plant Capacity Expected year

Puttalam coal power plant phase ii 600 MW 2014 Sampoor coal power plant 500 MW 2015

According to that coal power is becoming the main source of electricity generation, The Puttalam Coal Power plant is the first ever coal power plant in Sri Lanka, therefore that has an immense responsibility for electricity plan of Sri Lanka.

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44

The outcome of this project is to generate full load capacity from Puttalam Coal Power Plant throughout the year without any loss due to different weather seasons. According to past data of the last year, the generated power was 1,456 GWH but it can generate 1,512 GWH with the recommended coal for the different weather seasons, due to above loss of generation CEB lost about 4 million US$ for the last year. The rate of increasing price of coal is much more less than Petroleum oil therefore the economical benefit will increase in future.

Figure 8.1: Average price paid by UK power producers for coal, oil and natural gas 1999 to 2011(Department of energy & climate change, 2012) Table 8.2: Capacities and Average unit cost of thermal power plant

(System control CEB, 2012)

Thermal Plant Plant capacity _(MW) Average Unit Cost _(Rs/kWH)

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45

Figure 8.2: Coal is the Key to Affordable Energy (Plant fossils of West

Virginia, 2013)

Different coal types should be selected for rainy season and dry season to overcome that amount of loss as one option. Therefore it is recommended in this case the coal which has a calorific value of 6600 kcal/kg for rainy season and 6300 kcal/kg for dry season from above calculations. The boiler was designed for 5800 kcal/kg to 6900 kcal/kg range of Bituminous Coal. When introduce different type of coal to the plant it should be compatible for the plant equipments as below,

 Compatibility of main boiler  Compatibility of Coal Pulverizers  Compatibility of Coal Unloading

 Compatibility of Coal conveying system  Compatibility of existing coal yard capacity

The compatibility of the plant is mentioned under chapter 3.3 and chapter 4. According to that the recommended coal was compatible for the plant equipments.

Then according to the calculations for environment suitability in chapter 6, the emission of SO2, NOx and CO2 was within limit of environmental standards.

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9 REFERENCES

1) “Capacities and Average unit cost of thermal power plant” System control CEB, 2012.

2) China National Machinery & Equipment Import & Export Corporation. “Fuel specification coal analysis data “Technical Document for puttalam 1 x 300 MW coal fired power plant project, vol 1, Jan. 2006, pp. 42-43. 3) China National Machinery & Equipment Import & Export Corporation.

“Air to fuel ratio of coal mill”, Centralized control operation regulation of PCPP, 2012c for puttalam 1 x 300 MW coal fired power plant ,Rev. 3, June 302012, pp. 140.

4) China National Machinery & Equipment Import & Export Corporation. “Boiler specification”, Centralized control operation regulation of PCPP, 2012c for puttalam 1 x 300 MW coal fired power plant ,Rev. 3, June 302012, pp. 34.

5) CEB system control center, 2012 “Load Curve of Sri Lanka” daily report, March 8, 2012.

6) Control room PCPP, 2011, 2012 “Weekly Average Power Generation and Coal Consumption data” Historical data form control room puttalam coal power plant, April 2, 2012.

7) “Coal Unloader” captured from puttalam coal power plant, 2012.

8) “Coal handling system” Capture from coal control room of puttalam coal power plant, 2012.

9) Coal handling department, 2011, “Components at recommended coal” Report of coal specifications from Indonesia, 2011.

10) Department of energy & climate change, 2012, “Average price paid by UK power producers for coal, oil and natural gas 1999 to 2011”, https://www.gov.uk/government/uploads/system/uploads/attachment_d ata/file/65940/7341-quarterly-energy-prices-december-2012.pdf, Quarterly energy prices, dec. 2012, pp 28.

11) DGM PCPP, 2011 “Specified mill running conditions” Letter from Deputy General Manager.

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13) “Electricity plan of Sri Lanka” Generation plan of CEB, 2012.

14) Finance department PCPP 2011, 2012 “Coal price for the received coal” coal costing report of puttalam coal power plant 2011 & 2012, May 12, 2012.

15) Google map, 2012,” The distance to Puttalam coal power plant from puttalam town” https://maps.google.lk, April 17, 2012.

16) Google earth, 2010 “Location of puttalam coal power plant” Map downloaded: http://www.google.com/earth/download/ge/agree.html, April 17, 2012.

17) Lehigh energy update, 2006, “Use of power plant waseste heat to reduce coal moisture provides”, August 2006, Vol. 24 (2).

18) Longitude and latitude of Sri Lanka”

http://wiki.answers.com/Q/What_is_the_latitude_and_longitude_of_Sri_ Lanka, March 21, 2012.

19) Log book PCPP, 2011” commercial power generation of puttalam coal power plant” log book No: 01, 2011, pp. 64.

20) Manager of Puttalam coal power plan to Operation of Puttalam coal power plan, 2011.

21) Meteorological Department, Sri Lanka, 2012. “Average rain fall data for 30 years and Weekly average rain fall data from January 2011 to April 2012”repots from Meteorological Department. March 5, 2012.

22) “Plant performance and environmental benefits”, www.lehigh.edu, August 2006, Vol. 24 (2).

23) Plant fossils of West Virginia,” Coal is the Key to Affordable Energy”, http://www.geocraft.com/WVFossils/Energy.html , August 20, 2013 24) P.F. Odgaard, J. Stoustrup, and B. Mataji2007, “Preventing

performance drops of coal mills due to high moisture content” Proceedings of the European Control Conference , Kos, Greece, www.control.aau, July 2-5, 2007.

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26) “Sri Lanka DGP Growth rate”www.tradingeconomics.com, Feb. 13, 2013.

27) “Sri Lanka has different kind of load source”, http://en.wikipedia.org/wiki/Electricity_in_Sri_Lanka, Feb. 13, 2013.

28) Test report from SGS Lanka 2011, 2012)”Analyzed data of received coal to puttalam coal power plant” Fuel handling department of puttalam coal power plant, April 5, 2012.

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Appendix 1.1: Coal Consumption of Puttalam Coal Power Station

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Date _/(MW)Power Pressure _/(Mpa) Coal Flow _/(T/H) Temperature/_(C°)

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Date _/(MW)Power Pressure _/(Mpa) Coal Flow _/(T/H) Temperature_/(C°)

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(65)

58

Appendix 4.1: Cost of received coal to Puttalam Coal Power Plant