1

Feasibility Study Report

Krabi Coal-Fired Power Plant Project

Electricity Generating Authority of Thailand

Report No. 9A11 01 5702 Power Plant Development Planning Department.

KBCTH-P32-02 / 2012

October 2557

No.

2

Forward

The Electricity Generating Authority of Thailand (EGAT), a state owned utilities that performs the main tasks in the production and supply of electric power to meet the electricity demand of the people as well as responds to the economic and society development of the country. EGAT offers quality power system according to international standards, in the terms of stability, reliability with reasonable price. EGAT mainly concerns society and the environment when processes operations, also adheres to the principles of good corporate governance policy, good governance, transparency, morality, that can be verified and keeps in mind that EGAT is part of the society.

Power plant at Krabi has the net capacity to generate electric power of approximately 800 MW using imported good quality Sub-bituminous coal from overseas. This plant also uses modern equipment and technology for high efficiency in producing electricity along with stringent environmental management. Taking into account the feelings and needs of the community are also major concerns . The objectives are to accommodate the demand for electricity and enhance the stability of the power system in the South to meet the government policy in the term of fuel ratio distribution to produce electricity.

Executive summary

1. Background and objectives of the project According to the electric production capacity development plan of 2555 - 2573 (PDP

2010, 3rd revision) EGAT is set to construct 4 clean coal power production plants with the net capacity of 800 MW each and is scheduled to contribute power as commercial in 2562, 2565, 2568, and 2571, respectively.

Krabi power plant is the one in this area that has potentials to develop the coal-fired power plant projects since the area is the existing area of EGAT with infrastructure facilities and can support this development projects. This plant is also convenient linked to the main electric transmission system located at the center of power use in the South of Adamun coastline and there is the possibility to transport coal imported from abroad.

3

EGAT is then considering building this coal power plant with the net capacity of 800 MW within Krabi power plant area. The plant is scheduled to contribute power as commercial in in December 2562 using clean coal technologies that can control environmental impact in a very good way . As for the current Krabi power plant which uses fuel oil as fuel will run only for backing up the stability of power systems in the south. In order to build up confidence for community that the power plant uses modern technology with safety and met standards, expert staffs with experiences to supply power plant equipment for the group of countries with

stringent environmental and credible internationally, for example members of the Organization for Economic Co-operation and Development: OECD) are considered.

2. Project Description

2.1 Project Location Krabi coal power plants is located inside Krabi power plant T. Klong Ka Naan, A. Nau

Klong, Krabi province in the south of the existing power plant requires an area of about 600 acres and docks for unloading coal, located inside Baan Klong Rau oil depot (wharf unloading fuel oil for Krabi power plant) T. Talingchun, A. Nua Klong, Krabi Province away from the Krabi power plant about 9 km.

2.2 Types and sizes of the power. A thermal power plant of electric power base using imported coal as fuel with the

capacity to generate net electricity about 800 MW, an average efficiency through a lifetime of 30 years is approximately 41.34%. The powerhouse consist of main devices and systems including Supercritical Pressure Steam Generator, Steam Turbine Generator, Condenser, Cooling tower, Electrostatic Dust Trap (ESP), sulfur dioxide removal system (FGD), NOx removal system (SCR), docks, and coal conveyor system etc.

2.3 Fuel and Transportation The project uses good quality Su-Bituminous coal as fuel with average heat about 5,500

kCal./kg. (HHV), sulfur content no more than 1% for the average usage 7,262 tons/day or about 2.3 millions tons/year. This coal is. freight transported usinA 1-2 coal barges with the size about

4

10,000 DWT from aboard to Klong Rau dock per day. This coal is then loaded by conveyor system, 9 km. in length to coal storage building of the power plant with storage capacity of 480,000 tons and be able to reserve for usage about 60 days.

2.4 Water supply and water demand The project will use raw water from the reservoir of the plant for 3,830 cubic meters per

day to be used for steam generation process, sulfur dioxide removal, and other activities inside the plant. Water around 100,500 cubic meters per day from Klong Pakasai is also used for cooling system.

2.5 Power Transmission The project will link electric power to the main electric system at the 230 kW high power

station at Krabi. High power station is needed to improve and required construction of 230 kW transmission lines for 1 circuit and 300 m. in length.

2.6 The study to analyze the impact on the environment. Krabi coal power plant is a project that requires a report to analyze environment and

health impact (Environmental and Health Impact Assessment: EHIA) according to the Ministry of Natural Resources and Environment, dated August 31, 2553. EGAT has appointed Air Safe Limited to conduct a study and prepare a report analyzing the impacts on the environment and health (EHIA) from Krabi coal power plant project (extension 1) and present to the Ministry of Natural Resources and Environment to seek approval from the committee of experts to consider the report of the environmental impact assessment of thermal power plant. The report is also

presented to independent organization and agencies to consider providing additional opinions before presenting to the National Environment Commission for next approval.

The construction of a dock for unloading coal project is a project or action that need to be studied and prepared for a report about Environmental Impact Assessment: EIA according to the Ministry of Natural Resources and Environment dated June 20, 2555. EGAT has hired Team Consulting Engineering and Management Limited to conduct a study and prepare a report analyzing the impacts on the environment (EIA) from the Baan Klong Rua docking project ( docks and coal conveyor system) and present to Ministry of Natural Resources and Environment

5

to seek approval from the committee of experts to consider the report of the environmental impact assessment in the terms of water infrastructure before presenting to the National Environment Commission for next approval.

2.7 Project Plans The power plant project will take construction period of approximately 44 months after

issues Letter of Intent: LOI and is scheduled to contribute electricity to systems in December 2562.

The construction of docks and coal conveyor systems will take about 32 months after issues LOI and is scheduled for completion in December 2561, before contribute electricity to systems about 12 months.

2.8 Estimate the project cost s The project cost the total of 71,830.00 millions THBs, being the foreign currency

38,312.20 millions THBs and Thai THBs for 33,517.80 millions THBs as details below.

Categories Foreign currency Thai THB Total

A. Plant, millions THBs 34,497.00 22,033.00 56,530.00 Equivalent in $US, $ millions 667.60 1,713.00 1,045.00 B. Docks and coal conveyor, millions THBs 3,794.00 11,446.00 15,240.00 Equivalent in $US, $ millions 115.00 346.80 461.80 C. Transmission of electricity, millions THBs 21.20 38.80 60.00 Equivalent in $US, $ millions 0.60 1.20 1.80 Overall, millions THBs 38,312.20 33,517.80 71,830.00 Equivalent in $US, $ millions 1,161.00 1,015.60 2,176.60

Note: Use the exchange rate of 33 THB per $US.

6

The estimated annual disbursement are as follows.

Estimated annual costs 2559 2560 2561 2562 2563 Total A. Powerhouse 5,004.00 18,260.50 16,782.50 11,088.00 5,359.00 56,530.00 B. Docks and conveyors 2,546.00 5,547.00 5,271.00 1,876.00 - 15,240.00 C. Transmission system - 18.00 36.90 5.10 - 60.00 Total 7,550.00 23,861.50 22,090.40 12,969.10 5,359.00 71,830.00

2.9 Sources of Investment EGAT will consider financial status, capital market conditions, how to get a loan and

reasonable terms to get the maximum benefit by considering the sources of investment from EGAT income and from issuing bonds or loans from financial institutions as appropriate.

2.10 The Project Feasibility Krabi coal power plant project is a suitable project in the terms of policies, technical,

environment, economics, and financial as follows,. Policies: can support the power demand and strengthen the power system in the south

specially on the Andaman southern coast where the county tourism economy is growing with the continuous rate. This also reduces the risk of power outages from dependence on energy from the central region of Thailand because the restrictions on the transmission system. There are also less supply risks, price fluctuations and reduce the cost of electricity. It is the policy of the government about fuel distribution. Also, the large electricity generation sources for the south are primary depend on natural gas.

Technical and environmental: The project uses clean coal technology, a technology developed to control and protect the environment. This increases efficiency in electricity generation resulting in coal usage drop. Coal resources then can be used as cost-effectively and maximize the benefits. Environmental pollution control will be implemented at the beginning with the selection of quality imported coal. The transport and storage of coal use a closed system to reduce dust. The power plant will be equipped with modern and high-performance systems or devices to control emission to meet standards, includes monitoring, measuring and impact

7

assessment. The communities will be involved in the operation to have minimum impacts on the community and environment.

Economics and Finance: The project is worth the investment and provides a reasonable rate of return on investment. The project analysis are summarized as below.

The average selling price of electricity 2.4709 THBs / kW-hr. - The availability of electric power (AP) cost 1.0568 THBs / kW-hr. - Electric power (EP) cost 1.4141 THBs / kW-hr. Return rate on investment economically (EIRR) 10.17 % Present value of net benefits economically 8,302 millions THBs. Return rate on investment financially (FIRR) 10.17 % Present value of net benefits financially 8,059 millions THBs. Return on equity (ROE) 11.86 %. Present value of net benefits 6,267 millions THBs. Economic profit(Economic Profit) 4,695 millions THBs. Payback period 12 years

3. Benefits from the project 1) Strengthen the stability of the power system in the south . This can accommodate electricity demand adequately and reduce the risk of power outages from dependence on energy from the central region of Thailand that has the limitation of transmission systems . Also, purchasing of electricity from Malaysia is to be uncertain. 2) Reduce the loss of power due to transmission of electrical energy from the central region and increase the flexibility to control and contribute electric power. 3) The distribution of fuel to produce electricity corresponds to state policies for making the country's overall power generation system stability. 4) Create a balance between the proportion of electricity power plants of state generated and private power plant generated. 5) There are development of society, culture and way of life of the communities neighboring to the plant in terms of local development, education, health, and the environment as well as in disaster relief.

8

6) Power plants are education sources for energy and environmental management of the province.

4. Proposal to Consider The Krabi coal power plant is a project for energy security in the South. This can

continue building steps and complete as planned and agreed to take action for Cabinet approval as following.

1) Approval to construct and install Krabi power plants with the net electric production capacity of about 800 MW along with building docks and coal conveyor as well as power transmission systems. The amount of capital expenditure total 71,830.00 millions THB, in foreign currency THB 38,312.20 millions and THB 33,517.80 millions. 2) If the Cabinet approves the project, meaning to have approve the 2559 annual budget according to estimated plan spending for the project in the amount of THB 7550.00 millions by then.

3) To approve for spending investment sources for the cost in foreign currency from any source or multiple sources combined from international financial institutions, supplier's credit, buyer's credit, bank /export-import bank, bank/international financial institutions and/or local, issue bonds for foreign country investment, and/or local, and EGAT income for the cost of THB from one source or a combination of sources from banks/financial institutions in the country, bonds for investment in the country and EGAT income. 4) To approve the waiver of the Cabinet on 15th December 2530, on 23rd July 2534, 22nd August 2543, and on October 17, 2543 related to the mangrove areas for EGAT to perform the construction Krabi coal power plant, along with docks, coal conveyor and any other relevant in the mangrove areas.

5) To approve the relevant authorities allow EGAT to perform any activity of the Krabi coal plant project in the land of EGAT and state lands that asking for permits as necessary for the time being. Also asking for government supports, expedite approvals or permits mentioned to be completed as soon as for special cases. 6) To approve the Cabinet adopted on 11 July 2532 shall apply mutatis mutandis to EGAT to be able to pay compensation to the owners or occupiers of the land and property in and outside

9

areas of the bounds of official reserves but in the construction of Krabi power plants area. Lands or other properties must be occupied and taken advantages before starting the project.

1. Background

1.1 Background According to the electric production capacity development plan of 2555 - 2573 (PDP

2010 3rd revision) EGAT is set to construct 4 clean coal power production plants with the net capacity of 800 MW each and is scheduled to contribute power as commercial in 2562, 2565, 2568, and 2571, respectively to accommodate the demand for electric power and maintain stability of the power system of the country. It also meets the state policy on distribution ratio of fuel to produce electricity.

Krabi power plant is the one in this area that has potentials to develop the coal-fired power plant projects since the area is the existing area of EGAT with infrastructure facilities and can support this development projects. This plant is also convenient linked to the main electric transmission system located at the center of power use in the South of Adamun coastline and there is the possibility to transport coal imported from abroad.

EGAT is then considering building this coal power plant with the net capacity of 800 MW within Krabi power plant area. The plant is scheduled to contribute power as commercial in in December 2562 using clean coal technologies that can control environmental impact in a very good way . As for the current Krabi power plant which uses fuel oil as fuel will run only for backing up the stability of power systems in the south.

1.2 The electrical system situation in the South. The electric power generation capacity in the South in June 2557 is 2,115.68 MW net.

There is also backup power from the central through 600 MW transmission lines, ( normal situation) and 300 MW power from Malaysia was purchased (Non-firm agreement).

Overload power required in the South in 2557 (Peak Load) occurred on Tuesday, April 26, 2557 or 2,467.65 MW. At that time power generation sources in the south can be produced only 2,173.90 MW (Increased power production from the test, Ja Na power plant, unit 2 during the 8th of April to 23rd of May 2557), which is not enough to meet demand. Hence, there was

10

electric power sent from the central grid through central - south 265.65 MW transmission lines and from Malaysia (contractual) for 28.10 MW.

Details of electric power production in the south in 2557 and the power demand of the south by provinces are presented in Figure 1.1 - 1.2 and Table 1.1 - 1.2 A, respectively.

Natural gas termination from JDA-A18. Gas fields in the development in Malaysia - Thailand joint areas A-18 (JDA-A18) was

necessary to stop distributing gas during June 13 - July 7, 2557 to complete the installation of pressure increasing equipment and to connect more gas wells together. This results in Ja Na power plant unit 1, with 710 MW of net capacity while shutting down since this power plant received gas from a single channel and improvements of the power plant to be able to proceed with diesel that had not been completed. This caused the capacity of the South down to about 1,400 MW. EGAT then has prepared plans and policies to handle this situation.

The maximum demand for electricity in the South during the shut down occurred on 19th June 2557 which was equal to 2,339.96 MW. EGAT. had followed plans and policies with the conclusion as following,

1) Electric power through central - south transmission lines for 670 MW which was risky from exceeding electric stability standard N-1 Criteria (support when there was any one device failed).

2) Purchased electricity from Malaysia for Price B for 7.64 millions units and Price C for 2.94 millions units (Malaysian Electricity will inform the amount of electricity ready for EGAT each day depended on the Malaysian electricity system at that time. .

3) Run power plant which use fuel oil with high production costs and to enhance the power system including

3.1) Krabi power plant 315 MW.

3.2) Surat power plant 244 MW.

3.3) Diesel power generation 26 MW.

11

- The 15th Infantry Brigade, Pattani 5X2 MW.

- Chulabhorn Camp, Narathiwat 4X2 MW.

- High voltage station, Su Ngai Ko- Lok , Narathiwat 4X2 MW.

4) Coordinate relevant departments to help implement policies to reduce electricity demand (Demand Response) during that period. The Siam Cement of Thailand (Thung Song) Co., Ltd. (Thailand), a direct customers of EGAT has reduced electricity use by 10 MW per day.

1.3 Purpose of the project

To increase electricity production in the southern areas may just be enough to meet the demand, specially the Andaman South Coast which is a tourist economy area with a continuous rate of growth and increase the stability of the power system. This reduces the risk of dependence on electric power from a central transmission system or purchase electricity from Malaysia which is uncertain. This is also consistent with the government's policy on the

distribution ratio of fuel to produce electricity because the large size of power plants in the South rely mainly on natural gas.

Table 1.1 Net capacity of power generation from systems in the South, June 2557

Power plant Power Contract Fuel (MW) 1. Hydropower 313.28

1.1 Bang Lang Dam 72.00 -

1.2 Baan San Ti Dam 1.28 - 1.3 Rajjaprabha Dam 240.00 -

2. Thermal Power Plant 315.00 2.1 Krabi power plant 315.00 oil

2.2 Surat Thani power plant (gas turbine) - diesel. 3. Combined heat and power plants

3.1 The Ja Na power plant unit 1 710.00 Natural Gas

12

4. Renewable power plant 0.20 4.1 Laem Phrom Thep solar power plant 0.01

4.2 Laem Phrom Thep wind turbine power plant0.19 - EGAT Net capacity 1338.48

5. Small supplies (SPP) -Firm 29.00 5.1 Gulf Yala Green Co., Ltd. 20.20 timber debris 5.2 Surat Thani Green Energy Co., Ltd. 8.80 palm bunch

6. Major private supplies (IPP) - Firm 748.20 6.1 Khanom Electricity Generating Company Limited748.20

- Combined Cycle Power Plant unit 1 678.00 Natural Gas - Thermal power plants 70.20 Natural Gas/oil.

The power of the South generated 2,115.68 7. Backup electric generation that are reliable

7.1 Transmission Link Central - South (normal) 600.00 - 7.2 Transmission line linking

Thailand - Malaysia's 300 kV HVDC 300.00 -

Power Control Systems, Electricity Generating Authority of Thailand

Note: 244 MW Surat Thani power plant are out of the main system and has turned in to Emergency Standby.

13

Figure 1.1 Electric power generated for the South, 2557

14

Table 1.2 The maximum power demand of the South by Provinces.

Province peak electricity demand (MW) 26th of April,2557 2nd of April, 2556

1. Songkhla 481.7 480.1 2. Surat Thani 370.2 352.7 3. Phuket 373.4 5 359.3 4. Si Thammarat 314.7 330.9 5. Trang* 128.2 125.8 6. Chumphon 116.1 115.9 7. Krabi * 106.7 104.4 8. Pung Nga 95.9 98.6 9. Yala 96.8 87.5 10. Pattani 66.5 75.8 11. Phatthalung 74.1 61.3 12. Narathiwat 71.1 72.8

13 Stool* 56.3 59.8 14. Ranong * 47.7 46.2 Total 2,403.9 2,366.5 System power use and loss 63.6 57.3 Net 2467.7 2423.8 * Andaman southern coast provinces 807.7 805.5

Operations, Electricity Generating Authority of Thailand

15

Figure 1.2 Highest demand for electricity in the South by provinces

2. The purpose and scope of the study.

2.1 The purpose of the study

To study the feasibility of Krabi coal power plant by considering the possibility of implementing of the policy, technical, environmental, economics and, finance to comply with the policy of the state to meet the electricity demand of the country. This also includes the distribution ratio of fuel to produce electricity and strengthen the stability of the power system in the Andaman southern coast which all is risky and vital to the country. The process is to engage the public to contribute the understanding, acceptance and supporting in running the projects.

16

2.2 Scope of Study

The Feasibility study Krabi coal power plant project are along with the scopes to consider, as detailed below.

* Considering the location of the project.

* Considering fuel sources , fuel supply, and fuel transportation.

* Considering water sources, water supply, and wastewater treatment.

* Define the initial set of specifications.

* Considering transmission system of project and links to the main electrical system.

* Preliminary environmental impact study.

* Project implementation plan.

* Estimate project cost .

* Feasibility study of the process in the term of economics and finance.

3. Project Location

3.1 General

Krabi Power Plant located at 112 Moo 2. T. Klong Kanaan, A. Nua Klong, Krabi province on the area of about 6500 acres away from the Petchakasem road to the south, about 7 km. and around the borders of.

North: Moo 1 Ban Pakasai, T. Pakasai and Moo 4 Ban Khuan Yoong. T. Klong

Kanaan.

17

South Moo 6 Baan Klong Wai Lek T. Klong Kanan and Lam Kruad forest area

and Klong Bang Peung forest area.

East Klong Pakasai, next area are Lam Kruad forest area and Klong

Bang Peung forest.

West Moo 2 Baan Huay Soke. T. Klong Kanan.

Baan Klong Rua oil reserve is an fuel oil reserve and the port of Krabi power plant today. Located around Lam Hin headland, T. Talingchun, A. Nuaklong Krabi. Krabi away from the power plant to the south-west about 9 km. The area is about 98 hectares.

3.2 Location

EGAT has considered the location of coal power plant project within the area of Krabi power plant because the area was subjected to EGAT and allowed to take an advantage from the Forestry Department then there is no charge for the supply of land. There are also basic facilities necessary for developing the project as well as being ready to link to the main power system. In addition, there is the possibility to transport coal imported from abroad. The location is at the power used center of the South coast where are the tourist trades require increased electric power more and more every year. For coal unloading dock of the project, space around the oil depot of a power plant in Krabi will be used.

Project Location Map of Krabi coal power plant is shown in Figure 3.1.

3.2.1 Powerhouse Coal Krabi power plant is a thermal power plant with the net capacity of approximately

800 MW. This plant is located on an empty space inside the Krabi power plant and requires for an area of about 600 hectares, divided into three parts: 1) area for power generation, in the south and east of the existing power plant (fuel oil plant) of about 140 acres, 2) area of coal storage building, coal ash and gypsum disposal pond(Phase 1) on the south side of the Krabi power

18

plant of about 300 acres and 3) area coal ash and gypsum disposal pond(Phase 2) on the north side of the Krabi plant, about 160 acres.

The area around the Krabi coal power plant and coal storage building are shown in Figure 3.2 to 3.3

3..2.2 Dock

Dock for unloading coal for use as fuel for the project (Baan Klong Rua Dock) is located on the empty space inside the Baan Klong Rua oil depot which belongs to EGAT. This dock needs an area of about 45 acres for construction of port, coal handling systems, coal reserves building, and essential utility systems. The area around the Baan Klong Rua dock is shown in figure 3.4

3.2.3 Coal transporting conveyor

To transport coal from the dock to the plant, EGAT has chosen the conveyor system since it is a method that can continue transporting large quantities of coal. The defined route of this conveyor system will pass through T. Talingchun and T. Klong Ka Naan, A. Nuaklong Krabi with the distance about 9 km and the width about 50 m. The areas covered mostly are in national conserved forests that are utilized by communities for agricultural such as palm oil, rubber plantation, shrimp farming, etc. There are just some parts that pass through intertidal forests, natural canals, and public routes. However, to select coal conveyor routes, EGAT has tried to avoid the paths that pass through communities and intertidal forests or to have a minimal impact if necessary.

3.3 The use of state land

Project area is located within the borders of the state, such as national conserved forest, the agricultural land reform, wetlands, marine, public water supply or public thoroughfare. EGAT as a state agency can perform permission to use these area corresponding to the regulations and practices from the government agencies involved except the intertidal forests which according to the Cabinet as follows:

19

- Resolution of the Cabinet on December 15, 2530 entitled "The classify of the land used in the area of mangroves in Thailand."

- Resolution of the Cabinet on 23rd July 2534 entitled "Report on the current status of mangrove and corals of the country " by suspend the use of the forest is strictly prohibited."

- Resolution of the Cabinet on 22nd August 2543 "National Forestry Policy Committee of mangrove management solution" by prohibiting the use permit Mangroves in any case, both public and private sectors.

- Resolution of the Cabinet on 17 October 2543 "National Forest Policy Committee No. 3/2543 about mangrove management solution" by prohibiting the use permit Mangroves in any case. This includes the construction of infrastructure, and infrastructure for construction of treatment systems.

However, the project area, such as coal conveyor system that pass through the national conserve forests, the facts are that the areas are overrun by Rat to do agricultural work including oil palm plantations. As the access to the national forest land by the Forest Department regulations require that the applicant must have taken issue with the Rat invaders as well.

Cabinet resolution details related to land use are presented in Appendix B.

3.4 Climate Krabi coal plant project design uses climate statistics in the period of 20 years (since

2537-2556) of the meteorological station in Krabi. Table 3.1 shows the details

General climate around the project area are summarized below.

Dry bulb temperature (Ambient Dry-Bulb Temperature) - The maximum average 32.3 C - The minimum average 22.5 C. - Average 26.9 C

20

Relative Humidity - The maximum average 97.1% - The minimum average 62.6%. - Average 83.6%

Average atmospheric pressure 1008.98 mbar

Figure 3.1 Project Location Map of Krabi coal power plant

21

Figure 3.2 The area around the Krabi coal power plant

22

Figure 3.3 The area around the coal storage building

Figure 3.4 The area around the Baan Klong Rua dock

23

Table 3.1 The climate statistics in the period of 20 years (since 2537-2556) of the meteorological station in Krabi.

4. The supply of fuel and limestone 4.1 Properties and demand for coal The project will use Sub-bituminous coal as fuel which is the high quality coal, low

sulfur content by considering imported from the manufacturer and exporter of potential coal. There are enough reserves over the life of the plant and taking into account the management of transportation to be smooth and reasonable cost. Since the project is for the power system stability in the southern area, it is necessary to continue to supply coal in many

24

forms such as bid and EGAT continues to supply some of their own. In order to enhance the security of fuel supply. The properties of coal for use in the design are as follows.

Imported coal properties Design cost

Type of coal Sub-bituminous Higher Heating Value: HHV 5500 kCal./kg. Sulfur Content Less than 1% Ash Content No more than 10%

Moisture Content No more than 30%

Source: Preliminary properties of imported coal, fuel management. The Electricity Generating Authority of Thailand (2555).

The Krabi coal power plant project has the net electrical power generation of about 800 MW, a coal demand of approximately 7,262 tons/day or approximately 2.25 millions tons/year (at the rate of averaged running of 85 percent), operating a lifetime for 30 year, total project volume of coal approximately 68 millions tons.

4.2 Coal Transportation

4.2.1 Coal Maritime transportation from coal supply to the project dock. The project will use 1-2 coal barges with loading capacity of approximately 10,000

Deadweight Tonnage: DWT to transport high quality coal from overseas coal supply to the docks of the project, in the area of Baan Klong Rua oil depot per day using the existing route of the supertanker. However, barges need to wait for driven higher sea level when navigating through the mouth of the docks . Coal barge navigation is shown in Figure 4.1.

25

Coal barges are in-board engine barges with tonnage freight and a cap entirely. To help maintain the quality of coal by reducing dust and moisture, the ship is a steel shell boat, double hall, 120 m. in length and 30 m. in width, vessel size not less than 10,000 DWT, highest water depths up 5.5 m, but will carry coal to approximately 8,000 DWT only, where the water depths is 4.5 m. The safety allowances between the hull and the water bottom is 1 m. and lowest low tide (LLW) of Krabi estuary station, monitored by the Marine department is -2.4 m depth then the required depth is - 7.9 m from mean sea level as shown in Figure 4.2.

4.2.2 Coal transportation in the dock area.

New coal unloading dock for the construction of a new fence around the depot canal house. The L-shaped parallel to the oil dock unloading coal. The length of the coast is about 400 m long, 280 m deep berth at -8 m berth can accommodate vessels with tonnage of 10,000 DWT new coal unloading of two vessels simultaneously and the area behind the wharf for systems that are necessary with details as following,

1. Docks consiste of the berth width 30 m. with the length 280 m, and a bridge linked to the dock 380 m. in length. The dock floor is concrete pier with resistant to corrosion located on the round steel piles buried deep layer of clay or concrete deck on piles with walls prevent erosion.

2. Bank Protection placed parallel to the coastline wit the length of approximately 1,000 m. piling up certain size of stones with sand and cement and cementitious floor Riprap.

3. Two continuous screw type coal unloader or Bucket Chain Type Unloader number 2, Slashdot, each with unloading rate at least 1,500 tons/hr. The system works in a closed form, which can reduce the spread of coal with low noise levels in the workplace.

4. Storage building with the capacity of 50,000 tons of coal reserved for coal from the ship and stored temporarily in the case of conveyor belts to the power plant damaged or malfunction. Reclaiming Conveyor is mounted beneath coal reserves, air ventilation and dust trap system including spraying water to control the temperature and coal dust.

26

5. Office building , conveyor system control building, equipment storage room, equipment yard and green areas.

6. Utilities such as manholes, raw water reservoir, roads and parking lots, and so on.

Chart of the berths and coal loader are shown in Figure 4.3 - 4.5 respectively.

4.2.3 Transport coal from the dock to the plant.

Transportation of coal from the dock to the plant's coal storage building has the distance of about 9 km. using conveyor system. Since it is the proper way to transport large volumes over long distances that need continuity and reliability. In case of failure or malfunctioning conveyor belt and can not carry coal from the dock to the main coal storage building of power plants this will transport coal from the ship and take it to a temporary storage building coal reserves around the dock to continue unloading from ships. The routes and areas along the conveyor belt from the Klong Rua dock to Krabi Power Plant is shown in Figure 4.6.

Coal conveyor is designed as a closed system and cover all routes to control the spread of coal dust and noise with an average unloading rate of no less than 3,000 tons/hr. for a line width of 2.5 m., length of about 9 km. In the first 2 km., a tunnel will be constructed under Saba canal and mangrove areas to reduce the impact on the environment. For the last 7 km. will be the construction of the belt on the ground to coal storage building of the power plant. Structure and formats of the belt are as follows.

1) Conveyor belt in underground tunnels passing through the Saba canal and mangrove forests is about 2 km. including.

- Construction of concrete tunnel with the internal width 7.25 m., internal height 6.5 m., and the depth from the surface not less than 30 m.

- Ventilation and fire prevention systems. - Pipe Conveyor

2) Conveyor belt on the ground, from the underground tunnel to the storage building of coal power plant with the length about 7 km. and the right of way width of 50 m. , including

- Conveyor supporting concrete road with the width of 15 m.

27

- Public concrete road for the community, 6 m. in width on both sides along the conveyor belt.

- Box Culvert or concrete bridge or elevated structure along the public routes, natural water ways or obstacles on the ground.

- Sound Barrier and trees along the belt. - Conveyor in enclosure.

The structure and format of the conveyor are shown in Figure 4.7 to 4.10.

4.2.4 The coal storage building

The coal storage building is located from the south of the power plant for about 1.5 km. This area is about 100 Rais, and can accommodate up to 480,000 tons of coal to produce electricity continuously for about 60 days, including.

1) Coal storage building with covers, surrounding walls, and side enclosures around. Open only in and out ways of belts, including

- Two coal stock piles, each of 240,000 tons.

- Two combined stacker-reclaimers with the work rate of not less than 1,500 tons / hr. - Ventilation and coal dust trap systems. - Water spray system to control temperature and coal dust.

2) Two coal belt loader from a pile of coal maker and coal shoveling for delivering to the distribution bunker at the rate of no less than 1,500 tons / hr. 3) Utilities such as water reservoir for spraying coal piles. Waste water treatment system and waste water manholes.

4) Buildings such operational, maintenance, material storage, and conveyor belt control buildings.

The coal storage building is shown in figure 4.11.

28

4.3 The sources and the needs for limestone. The project requires good qualities of limestone with the content of CaCO3 of at least 90

percents for the removal of sulfur dioxide from the burning of coals with the maximum rate about 240 tons/day or 74,460 tons/yr. The total limestone required over the life of the power plant for 30 years is 2.23 millions tons by purchasing limestone from private sources in Thung Song, Nakhon Si Thammarat., about 123 km.from the power plant. With the reserved amount of limestone about 16 millions tons, this can meet the needs throughout the life of the project. This must be purchased for the power plant for system running test in December 2561 before the schedule to supply electricity to the system for the period of 12 months.

29

Figure 4.1 Coal Barge Navigation

30

Figure 4.2 Coal Barge

31

Figure 4.3 Chart of Baan Klong Rau dock

32

Figure 4.4 Screw Unloader

Figure 4.5 Bucket Chain Unloader

33

Figure 4.6 The routes and areas along the conveyor belt

34

Figure 4.7 The tunnel structure for coal transportation

Figure 4.8 The loading conveyor structure on the ground

35

Figure 4.9 Pipe Conveyor

Figure 4.10 The coal storage building

36

Figure 4.11 Coal Barge Navigation

5. The water supply, storage and wastewater treatment.

5.1 Water resources and water delivery systems. The project will take water from the same sources of Krabi power plant that currently

uses which is enough for the project even combined with existing power plants. The water for cooling process is taken from the Chaya canal but pumping is performed during high tide, which has the time limit. Because the Chaya canal, in the power plant area is in the influence of fluctuations of the ocean. Also, the pumping water from canals has the direct the impact to the community. Therefore, the construction of canals to draw water with the low current flow during the high-tide before pumping is considered. The details are as follows:

37

- The canal to draw water is a dug canal in a rectangular shape built with concrete. The width of 18 m., length is about 750 m. The canal ground level is at - 3.50 m., while the water minimum level of Klong Pakasai is at - 2.40 m. The water flows continuously by gravity and high-tide, low-tide level.

- Control the water to flow no more than 0.1 m./sec but since the speed of precipitation is 0.6 m/sec this causes sediment before reaching the pump, especially at the mouth of the canal, then a sediment trap (Settling basil) at upper canal is required.

- Install a 5 cm2 trash rack and a 1 cm2 rack as the 2nd layer to prevent aquatic life, specially aquatic larvae to flow into the cooling ponds.

- Pumping station is equipped with 2 water pumps (reserve 1).

Water used in production processes and consumption is taken from the reservoir of the Krabi power plant, including.

- Reservoir 1 (Inner), located inside the plant, about 500 m. from the previous plant to the South. The average amount of water flowing into the basin is about 0.177 billion cubic meters of the capacity 0.316 millions cubic meters. The pumping station is installed at this location to be used within the plant.

- Reservoir 2 (Outer) located to the Northwest of the previous power plant, with the average amount of water flowing in per year of 2.771 millions cubic meters of capacity to 1.82 millions cubic meters. This is the main raw water reservoir of the power plant. Water from the reservoir 2 is drained to fill the reservoir 1 through connected natural canals.

There are also other water resources.

- Baang Pu Dum Reservoir located to the North of the power plant. The reservoir is caused by an old mine pit lignite with capacity 7.227 billion cubic meters. The average annual inflow water is 0.314 billion cubic meters and currently is used for trees in the Krabi power plants and can be mixed with raw water from the reservoir for use in part of Sulfur Dioxide removal of some existing power plants.

- Baang Yaang canal dam is a weir dike dam construction project to raise the water level in the Baang Yaang canal and pump water during the rainy season to store in the power plant's

38

reservoir to strengthen the Krabi power plant. The structure is concrete with the length of about 40 m., height of 2 m. and can store the water level 4.5 m. (Geographical restrictions, making water storage at a low level) or water of 0.11 millions cubic meters. The average amount of water inflow to the dam each year is about 7 millions cubic meters. By installing 2 water pumps (reserve 1) to pump water through a 500 mm diameter, 3.75 km. in length pipe to the reservoir 2, due to the volume of the tub is enough to hold the water before discharged through natural canals into reservoir 1.

The pumping will be carried out during August December, 8 hours per day at the rate of 864 cubic meters per hour. The guidelines for pumping water from Baang Yaang canals, dam are shown in the table below

Unit: cubic meters per hour

Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar - - - - 864 864 864 864 864 - - -.

Water resources and the delivery guidelines of raw water of Krabi power plant are shown in Figure 5.1 to 5.8.

5.2 Water Requirement Power plant requirement for water activities is divided into 2 parts, water used inside

power plants, about 3,830 cubic meters per day which includes water used in the production of steam and activities inside the plant as well as water used for removal of sulfur dioxide. Raw water is used for heat removal or water cooling which is approximately 100,500 cubic meters per day. This is designed to circulate water for reuse. However, some water evaporates causing water in the cooling system has a higher concentration and need to drain some of the water out and into the offset to prevent corrosion and fouling in pipes and fitting systems . By designing, the cycles of concentration index will not exceed 1.5.

39

Water requirement for the project

Unit: cubic meters/day

Activities(water resources) maximum water required 1. Raw water for use in power plants (reservoir of the power plant) 3830 - Steam production process and activities inside the powerhouse 1200 - Sulfur dioxide removal system. 2630 2. Water used in cooling systems (Pa Ka Sai canal) 100,500

Note: Effluents from various activities of power plant (fresh water) after the treatment and discharge of waste water into the reservoir 1, then will be reused in the management of heavy coal ash system and coal dust yard control.

Water mass(weight) balancing of Krabi coal power plant project diagram is shown in Figure 5.9.

Considering the demand for water after the project was completed combined with the needs of the existing power plant when running processes at full capacity of 340 MW and water production data by Krabi plant, the water demands of the Krabi power plant after the project was completed are as follows.

Unit: cubic meters per day

Activities Existing Krabi plant Coal power plant Total

1. Raw water for use in the power plant 3732 3830 7562 - Activities in the powerhouse 1920 (1) 1200 3120 - Removal of sulfur dioxide system 1172 (1) 2630 3802 - Water Supply 640 (2) - 640 2. Water used in the cooling system 54,000 (1) 100,500 154,500

40

Source: (1) Water balance sheet for existing Krabi power plant. (2) Total water used by Krabi power plant statistics, 2555, Krabi power Plant, Electricity Generating Authority of Thailand

5.3 Water Treatment

Water used for activities inside power plants, water used in the production of steam, water consumption and internal power plant consumption will be taken through a process to adjust the water quality suitable to be used in various activities.

Water treatment process consists of fine filtering (Microfiltration, MF), the size 0.1 micron filtration without addition of chemicals to precipitate. The water is then filtered to be water with a Turbidity no more than 0.1 NTU and Silt Density Index (SDI) no more than 3 to be consumed. This is also a substrate in the demineralization system and Reverse Osmosis/ Electrodeionization (RO/EDI) to prepare to be qualified pure water without any suspensions, preventing fouling on the walls of the pipes within the steam generator, including the elimination of substances that may be harmful to the turbine blades and water feeding system for condensing.

The coolant will be filled with chlorine in the proper control amount in order to prevent the adherence of fish larvae and barnacles in the cooling system only, this also control the amount of chlorine in the water that are flowing out of the system (residual Chlorine) to comply with the effluent standard which is no more than 1.0 milligrams per liter.

5.4 Storage and treatment of wastewater.

Effluent from the power generation process of the project will go through the process of containment and treatment as follows.

41

5.4.1 Effluent from power plants.

1) Water from the water production system at the rate of 87 cubic meters per day is a chemical-free water. However, there are more water-soluble salts (TDS) in this water than fresh water.

2) The effluents from demineralized water supply system in the Brine rejection are at the rate of 273 cubic meters per day. A chemical-free water, but with TDS higher than fresh water.

3) Wastewater from steam generation system from Condensate Polisher a rate of 40 cubic meters per day is chemical-free water but has higher TDS than fresh water.

4) Chemicals -contaminated effluent with the rate of 28 cubic meters per day is effluent from mineral-free water production system. Effluent from Condensate Polisher system when chemicals are applied and effluent from chemical lab will be treated in Neutralization basin to adjust base-acid using hydrochloric acid or sulfuric acid and sodium hydroxide to have pH in the range of 5.5-9.0 as the benchmark of effluent.

5) Effluent from general use and consumption with the rate of 35 cubic meters per day will be treated together in Septic tank system which has been designed to handle BOD5 about 200 mg / liter. Water after this treatment will have BOD5 less than 20 mg. / liter as the standard of effluent.

6) Effluent contaminated with oil is the effluent from washing, cleaning up tools and equipments with oil contamination and with the rate 43 cubic meters per day. This effluent will go through the process of extracting the oil using oil/water separator which end up with the oil contamination not exceed 5 mg./liter as the benchmark of effluent.

Effluent from activities inside power plants for 506 cubic meters per day after gone through the treatment and meet the standard quality level will be brought together in the effluent clarifier 1 (Holding Pond -1) with the capacity of about 1,000 cubic meters, the depth of about 3 meters of concrete paving to prevent leakage of water into the groundwater layer. The construction area is about one hectare of water in the reservoir which will be used in the management of coal ash and coal dust clarifier for treatments using wastewater treatment system then recirculated for new applications. The sludge formed will be dumped in sludge landfill.

42

5.4.2 Waste water from the cooling tower. The coolant in the cooling system after passed through the condenser will be discharged

to the cooling tower to reduce the temperature and then circulated back into the cooling system again. The fans in the cooling tower remove heat in the water. Some cooling water lost to evaporation and spray. The water remaining in the system then are highly concentrated with solutions (TDS) and suspended solids (TSS) requiring to drain some water out (Blowdown) and add some water to replace (Make up) to prevent corrosion and fouling in pipes and fittings.

The water drained from the cooling tower has high concentration of solutions than normal and the temperature is controlled not to exceed environmental standard then will be taken to the pond effluent -2 (Holding Pond-2) to adjust the temperature to be as close as possible to environment temperature before released back into the Pa Ka Sai canal. This is done by the construction of a new water reservoir on a blank area of 30 acres, East of the existing Krabi power plant. Pond bottom is compacted and compressed soil lined with concrete sides. The depth of the pond is about 4 m., with the capacity of approximately 70,000 cubic meters and can accommodate wastewater from the cooling tower for about one day before draining into Pa Ka Sai canal using gravity through 1200 mm. diameter and 500 m. length pipes.

In summary, the amount of effluent from the project from power plant's activities are as follows.

Activities(water resources) maximum amount of effluent. 1. Effluent from the plant's activities 506

* Water production system 87 * Demineralization Plant 273

* Steam cycle 40

* Amphibious pond 28

* Wastewater treatment tank 35 * Oil - Water separation 43

2. Cooling Tower Blowdown 66,960

Note: No water from sulfur dioxide removal process due to completely evaporate

43

5.5 The use of Dock.

5.5.1 Water demand and water resources of the Dock.

At harbor areas, a demand for fresh water for consumption of berth staff (including existing oil dock staffs) and staffs on the coal barges is about five cubic meters per day. Also, spraying water used in reserved coal storage building is about 90 cubic meters per day, results in the total of 95 cubic meters per day, or 2,850 cubic meters per month.

The project will construct a pond to store water in the dock with the capacity of 10,000 cubic meters for the storage of rainwater, including water and wastewater treatment pond to circulate water used. Considering rainfall statistics from Table 5.1, the lowest rainfall was 25.9 mm. on January. When consider runoff water flowing into the pond, and provision for losses, 3,263 cubic meters of water can be seen that in the month with the lowest rainfall, runoff water flowing into the pond is enough for all of the dock.

Table 5.1 The average monthly rainfall statistics in Krabi, 2555

Code catchment area, the average monthly rainfall - mm annual precipitation: mm.

Province km2 Apr May June July Aug Sept Oct Nov Dec.

Source: Irrigation water monitoring stations.

5.5.2 Storage and Wastewater Treatment of the Dock.

Waste water from coal transportations and coal unloading around the dock area will be treated and stored as follows

1) Water from the general use and consumption all will be treated in the septic tank which is designed to handle BOD5 about 200 mg/liter. Treated water will have BOD5 not exceed 20 mg. / liter which met the effluent criteria.

44

2) Waste water from coal dust removal system, coal wasted contaminated rainwater, and fire suppression systems all will be directed to the drain rail systems that are around the project and machine installation areas then flows into the reservoir sedimentation coal to prevent this flowing to public water supplies.

3) Wastewater contaminated with oil is the waste water from washing and cleaning equipment and tools with oil contamination. This wastewater will be separated from oil using oil /water separator, results in contaminated with oil, no more than 5 mg/liter to meet effluent criteria.

All waste water after treatment to meet the standard and quality will be included in a holding pond of the dock with the capacity of 9000 cubic meters of all concrete paving. To prevent leakage of water into the groundwater layer after treating this effluent, all will be recycled back in control coal dust or for watering trees around the dock. The sludge will be dumped in landfill sludge further.

45

Figure 5.1 Water resources around Krabi power plant

Figure 5.2 Raw water delivery guidelines for Krabi power plant

Figure 5.3 Water resources of Krabi power plant

46

Figure 5.4 Reservoir 1 (Inner)

Figure 5.5 Reservoir 2 (Outer)

47

Figure 56 Bang Yang canal

Figure 5.7 Bang Poo Dum reservoir

48

Figure 5.8 Pa Ka Sai canal

49

Figure 5.9 Water mass(weight) balancing of Krabi coal power plant project diagram

50

6. Basic technical details of power plants

6.1 Clean coal technology for Krabi coal power plant projects

Clean coal technology is the technology that has been developed for highest benefit use of coals in the form of fuel as well as to control pollutions to have minimum impacts to

communities and environments. Currently there are many options of technologies for generate electricity using coals which can process before combustion, combustion, and after combustion. This project utilizes modern coal technology that offering both safety and suitability as follows

1. Clean coal technology before combustion Select good quality coal resources that have cleaned up or made coals to be free of contaminations. Configuration and monitoring before accepting the coals including transportation, storage, and transport to the power plants and operated by the closed system should be done as possible to reduce the spread of coal dust and noises that might have impacts to communities and environments.

2. Clean coal technology during coal combustion.

Select high efficiency of combustion and steam generations technology for coal maximize the usage and reduce pollution while burning.

- Pulverized-coal combustion: PC technology is the coal combustion method with the highest efficiency and is widely used in producing electricity from coal. This is done by grinding the coal to be small as the dust before spraying into the furnace with air. When flammable coal is heating the high pressure steam generator, the steam will spin the steam turbine that connected to the shaft of the generator.

- Low NOx Burner (LNB) and Over Fired Air (OFA) technology using the Mutistage burner and use more air than in the combustion reaction to reduce temperature and time of the burn that generates NOx.

51

- Supercritical boiler (Once through boiler) technology produces steam at higher pressures and temperatures than from the Sub-critical boiler. This is done by changing water to be super critical steam without using a boiler drum, but required special materials that can withstand such temperatures and pressures. It is then a highly effective technology, low fuel burn, and CO2 emissions. The efficiency of electricity production depends on the state of steam.

3. Clean coal technology after combustion Select air quality control technology after combustion, cost controlled after burning with

up-to-date and high-efficiency technology that includes electrostatic precipitator: ESP, sulfur dioxide removal system using limestone, elimination of oxides of nitrogen, and a selective catalytic reduction (SCR) type.

6.2 Technical specifications of the power plant Krabi coal power plant, a thermal power plant is producing power base using imported

coal from overseas for fuel with the net 800 MW electricity generation capacity, 42.16 % efficiency (new and clean) and approximately 41.34 % of average electricity generation efficiency for the lifetime of 30 years. Powerhouse consists mainly supercritical pressure steam generator, steam turbine generator, condenser, cooling tower, ESP, FGD, SCR, etc.

There are also auxiliary systems such as water treatment plant, waste water treatment

systems, coal handling system, and ash and Gypsum handling systems. The power plant is a thermal power plant. The thermal energy from burning coal

produces high pressure steam in order to drive a steam turbine to produce electricity. Steam, after being used in the steam turbine for power generation will be transformed into recycled water to be used in the production of steam again by passing steam into the condenser which uses water from outside sources as a cooling. High temperature cooling water from the condenser is then cooled down by a cooling tower before returning back to water resources. The exhaust from the steam generator is vented out through the chimneys of the power plant. This gives better amount of sulfur dioxide (SO2), nitrogen oxides (NOx) and dust control than the standard limit.

6.3 Introduction to electrical technical performance data of the power plant

The project has the technical performance data of the initial electric power plants below.

52

53

54

The Typical Cycle Heat Balance diagram of the Krabi coal power plant project is shown in Figure 6.1

6.4 The main equipments of the power plant

Coal power plant project, Krabi. consists of main equipments as follows

6.4.1 Supercritical Pressure Steam Generator

This steam generator is sliding pressure operation type to produce steam using Supercritical Once Through, a process which is the modern technology. This steam generator has a steam generation capacity of 2270.90 tons per hour at a pressure of at least 260 Bar (a) and a minimum temperature of 566 C.

6.4.2 Steam Turbine Generator

This steam generator is a Triple-Pressure type with main components., high-pressure

turbine, intermediate-pressure turbine, and low-pressure turbine that are installed in series (Tandem Compound). The steam from the high pressure steam turbine will be heated up again(single-reheat) at the steam generator prior fed into the medium pressure steam turbine. After the steam passes through a set of blades, the temperature and pressure will drop. Finally, the water will flow out of the low-pressure turbine and then flows into the condenser.

The steam turbine will drive a generator, 2-Pole Synchronous type , cooled down by hydrogen or hydrogen and water through the stator coils with a capacity of electricity net about 1024 Mega Volt - Ampere at the power factor of 0.85 lagging, voltage 18-24 kV, frequency 50 Hz, 3 phases, and rotation speed of 3,000 rpm. The electrical energy produced is sent to the main generator transformer to raise the voltage of 18-24 kV to 230 kV. and sent to high voltage terminals.

55

6.4.3 Condenser

A tubular surface heat exchanger s condenses steam from the steam turbine and turn into water to be circulated back into the steam generation system again.

6.4.4 Cooling Tower

A Mechanical draft, counter flow cools down high temperature coolant from the condenser before draining into the sewer manholes.

6.4.5 Electrical Equipment

The main equipments are

1) Transformer serves to raise the voltage from the generator to supply power to the 230 kV transmission system.

2) Circuit Breaker and Switchgear to connect/disconnect electric circuits.

This also includes Bus bar, motors, etc.

6.4.6 Control and Instrumentation

The main components are

1) DCIS (Distributed Control and Information System) system control room, serves as a control center for equipment operations in the power plant such as supercritical pressure steam

generation, steam turbine generator, and balance of plant.

2) Computer room serves as a recording and calculation center.

3) Electronic and Relay room serves as a equipment center to control the main systems of the power plant.

56

6.4.7 NOx Reduction Systems

For a power plant design, the combustion technology and Low NOx Burner (LNB) and Over Fired Air (OFA) and the removal of nitrogen oxides using Selective Catalytic Reduction (SCR) are considered as follows:

1) Low NOx Burner (LNB) and Over Fired Air (OFA) technology using the Mutistage burner and use more air than in the burning reaction to reduce temperature and time of the burn that causes NOx.

2) Install the removal of oxides of nitrogen system with Selective Catalytic Reduction (SCR), which is the removal of oxides of nitrogen (NOx) from the exhaust by using a chemical reaction between ammonia (NH3) and nitrogen oxides. A catalyst change NOx to be water and nitrogen (N2), which is a typical element contents of air. Ammonia used may be in the form of Anhydrous, Aqueous Ammonia, or Urea. Ammonia will be mixed with hot air in the proper ratio before sprayed(vaporizer) into a reactor with a layered catalyst to capture the NOx in the exhaust, resulting a reaction as follows:

NO + NO2 + 2NH3 2N2 + 3H2O.

The removal efficiency of nitrogen oxides is at least 76.63% . NOx removal rate can be controlled to be a specific value but will not exceed 70 ppm.

6.4.8 Electrostatic Precipitator: ESP

Exhaust that has gone through the SCR system then is sent to the Electrstatic

Precipitator: ESP, which is a device used to trap dust and fly ash, relies primarily on the electric potential difference for dust separation. This exhaust is then passed through a chamber packed with flat metal plates placed in parallel, with equally vertical spaced and wires situated halfway between these sheet metals. When these wires are supplied with high direct current, causing these wires to have negative electric potential and metal plates to have positive electric potential. When the dust and ash pass through, the dust particles are induced negative ions and trapped on the positive electric potential metal plates. When the amount of dust settles on the

57

plates enough, they are needed to be remove down the holding cone at the bottom of the chamber. Fly ash caught up with ESP will be transported by air pipe system to the fly ash silo and wait for further transportation.

Dust and fly ash trap efficiency is at least 99.67 % and can control dust removal into the atmosphere to a maximum of 30 mg. per cubic meter.

6.4.9 Flue Gas Desulfurization: FGD

The system eliminates sulfur dioxide and wet limestone, which use limestone to capture sulfur or dioxide from the flue gas of power plants as the same as FGD system that Krabi power plant are currently using limestone, CaCO3, an average of 240 tons per day that grounded to a certain size and mixed with water then sprayed into a absorbed tower with the exhaust flow in the opposite direction to be reacted with sulfur dioxide in the exhaust and turns to synthetic gypsum, gypsum, CaSO42H2O and will be stored in a gypsum silo to wait for further transportation.

Sulfur dioxide removal efficiency is not less that 94.13% and can control expendable of sulfur dioxide according to the defined values, not more than 50 ppm.

6.4.10 Water Treatment System

To adjust the water to suitable qualify for each activity including service water system and demineralization system for the steam production.

Water system for consumption use a fine filtering process (Microfiltration, MF), with the filtering size of 0.1 micron filtration without addition of chemicals to precipitate. The filtered water is then become tap water with turbidity less than 0.1 NTU and the silt density index (SDI) less than 3 for consumption. This water is also being the first water in the demineralization water production system with reverse osmosis/electrodeionization (RO / EDI) for filling the boiler in the steam production.

58

6.4.11 Coal Handling Systems

Coals from distribution bunker coal shipped from the coal storage building will be transported by the main conveyor and taken down to sub conveyor to the steam production building steam to fill each coal boiler bunker. Coals from the coal boiler bunker will pass through a coal feeder which serves to control the amount of coal to be suitable for crushing coal pulverizer and turn into a fine powder for the right size for burning later.

The project uses coal as fuel for about 300 - 400 tons / hr., but for the stability of the reactor to produce electricity, coal conveyor other equipment will be designed to transport coal of about 600 tons / hr. There is also a standby conveyor system for one set.

Construction and installation details of coal conveyor.

- Construction of distribution bunker building with the capacity of 2,000 tons.

- Construction of two coal main conveyors from the distribution bunker building.

- Construction of two boiler bunker conveyors to steam production building to transport coal

and fed into coal boiler bunker.

6.4.12 Ash and Gypsum Handling Systems

The system transporting coal ash and gypsum which is the by products from coal combustion and sulfur dioxide removal system are as follows.

1) Bottom Ash Handling System. Bottom ash at the bottom of the combustion chamber with the volume of 145 tons/day are transported by conveyor system to store in the bottom ash dump pond that has been prepared.

2) Fly Ash Handling System. Ash trapped by dust trap equipment using ESP in the amount of 579 tons/day will be transported by pneumatic and stored in the Fly Ash Silo, which has the storage capacity of not less than 12 hours of production or approximately 300 tons and waiting to be transported by truck to dispose to fly ash retention pond that has been provided.

59

3) Gypsum Handling System. Gypsum generated from sulfur dioxide removal system in the amount of 463 tons/day will be transported by conveyor belt to a gypsum storage building and waiting to be transported by truck to a gypsum tank that has been prepared.

6.5 Map of power plants

Coal power plant at Krabi. uses area for the construction of power generation and transmission system on the south side of the existing Krabi power plant about 140 acres consists of supercritical pressure steam generator, steam turbines , control, and electrical generator system, electrostatic dust capture system , Sulfur dioxide removal system, Nitrogen oxide removal system and the cooling tower as well as space for the storage of coal and by product material. Also, approximately 460 hectares consists of coal storage building, gypsum disposal pond, fly ash disposal pond, and bottom ash disposal pond.

Chart of the coal power plant project at Krabi, chart of the coal yard and chart of Krabi coal power plant are shown in figure 6.2 to 6.4, respectively.

60

Figure 6.1 Heat balancing chart of Krabi coal power plant

61

Figure 6.2 Chart of the coal power plant project at Krabi

Figure 6.3 Chart of the coal yard

62

Pls. get the additional figure from the company(too big)

Figure 6.4 Chart of the coal power plant project at Krabi

7. Electrical Power Transmission System

7.1 Transmission System at Krabi.

Currently, the transmission system within the province of Krabi, includes high voltage booster station at 230 kV linked to another high voltage stations using transmission lines (Figure 7.1) as follows.

1) High voltage stations, 115 kV.

* Krabi (KA) - Lamphu Ra (LR), single circuit, line size 150 Sq.mm AAC for 85 km.

2) High-voltage stations, 230 kV.

* Krabi (KA) - Phang Nga 2 , dual circuit, line size (PN2) 2X1272 MCM ACSR for 98 km.

* Krabi (KA) - Thong Song 2 (TS), line size 1272 MCM ACSR for 79 km.

7.2 Electrical Power Transmission System for the project.

The project will link the electrical power generated to the main electrical system or a high voltage power station 230 kW at Krabi (Figure 7.2). The existing power transmission system can accommodate the generated power capacity of approximately 1,040 MW, while the project has the net capacity of 800 MW. The existing power plant at Krabi has the net capacity of 315 MW, hence.

63

1) If the existing power plant is for a backup power plant Cold Standby.

The standby electrical systems can accommodate standard N-1.

2) In case of the existing power plant at Krabi run along with the project.

Existing power plants can run at the net electrical capacity of no more than 240 MW.

Scope of transmission system for the project includes,

1) Construction of the 230 kV transmission line from the power yard of the project to a high voltage, 230 kV power station at Krabi with single circuit, line size 4X1272 MCM ACSR per phase for 300 m. as well as installation optical fiber in the overhead ground wire.

2) Extend the high voltage, 230 kV station at Krabi to accommodate 230 kV transmission lines from the project for one circuit.

Construction period of the power transmission system of project from preparation until completion is approximately 35 months and is scheduled for completion in December 2561 before the plant is completed approximately 12 months in order to support equipment testing of this power plant. Detailed plans for the construction of power transmission system is shown in Figure 7.3.

64

Figure 7.1 Map of Electric Power system in the south

65

Figure 7.2 Chart of Electric Power system linkage of the coal power plant project at Krabi

66

Figure 7.3 Plans for the construction of power transmission system of the Krabi coal power plant project

67

8. environmental impact study

8.1 General

Krabi coal power plant project is a project that has to prepare a concerning environments and Health Impact Assessment: EHIA) according to the Ministry of Natural Resources and Environment, dated August 31, 2553 entitled "Determine the type, size, and practices or activities of the project that may cause a severe impact on the community both quality of the environment, natural resources, and health. The official organizations or private enterprises must do the environmental impact assessment 2553 " For the power plants that use coal as a fuel with the capacity of more than 10 MW, these plants shall prepare a report analyzing the impact on

environment as stated by the Ministry of Natural Resources and Environment in the terms of defined rules, procedures, policies, and regulations and guidelines on environmental impact assessment report for projects or activities that might cause serious impact on the community. The quality of the Environment Resources and Health, dated December 29, 2552.

The EGAT has hired Air Safe Limited to the study and provide a report analyzing the impact to environment and health (EHIA) from the power plant in Krabi (extension 1) and presented to the Office of Policies and Natural Resources and Environment planning to request an opinion from the expert Committee to consider this analysis report of environmental impact of thermal power plants and let independent organization and government agency authorizing to add opinions before presenting to the National Environment Board to approve next.

The Klong Rua Docking project is a project or activity to study and prepare a report to analyze the impact on the environment. (Environmental Impact Assessment: EIA) for the Ministry of the Environment and Natural Resources, Government of June 20, 2555. This is for the docks that support the ships more than 500 gross or berths length of no less than 100 m., a dock with the total area of 1000 square meters up. The EIA report must be prepared in accordance with the regulations and guidelines for the preparation of the Environmental Impact Analysis of the Department of Environment and Natural Resources.

68

The EGAT has hired TEAM CONSULTING ENGINEERING AND MANAGEMENT Limited to carry out the study and prepare a report on the Environmental Impact Assessment (EIA) projects of the Baan Klong Rua docking project . The scope of the construction of a dock and coal conveyor system are including the transport of coal by sea through the country. However, EGAT has realized the benefits of education and the process of public hearings then has set up a study and prepare the EHIA report and presented in accordance with the Natural Resources and Environmental Policy and Planning Office to request an opinion from the Committee of experts to consider the environmental impact assessment report in the terms of water Infrastructure Before presenting to the National Environment Board for approval next.

8.2 Environmental Standards

To carry out the project, various up-to-date environmental control systems with minimal environmental impacts will be selected . The environmental standards involved are as the followings

8.2.1 Air Quality Standards

- In general, Air quality standards according to the National Environmental Board No. 10 (2538), dated April 17, 2538, No. 21 (2544), dated April 9, 2544, No. 24 (2547. ) dated August 9, 2547, and No. 28 (2550) dated April 10, 2550.

- Air Emission Control Standard for dumping waste from new power plants that are licensed to operate the factories or licensed for plant expansion on January 16, 2553 according to the Ministry of natural Resources and Environment about the standard for controlling the Emission level from new power plants, dated December 20, 2552.

8.2.2 Sound Level Standard

- In general, sound level standards according to the National Environmental Board No. 15 (2540) Standard for volume generally dated March 12, 2540.

69

- Noise level standards are according to the Board of the National Environmental about Noise level No. 29 (2550) dated 29 June 2550 and the Ministry of Industry on the noise level and the noise caused by the operation of the plant (BE 2548), dated December 27, 2548.

8.2.3 Vibration Level standards to Protect Building Impact

- The vibration level standards to protect the building are according to the National Environmental Board No. 37 (2553) dated April 26, 2553.

8.2.4 Water Quality Standards

- Water quality standards from industrial and industrial parks according to the Ministry of Science Technology and Environment, No. 3 (2539), dated January 3, 2539, the Ministry of Industry No. 2 (2539), dated 14 June 2539, and the Marine Department at 419/2540 dated 22. August 2540

- Water quality standards in surface water according to the National Environment Board No. 8 (2537), dated 20 January 2537.

- Groundwater Quality Standards according to the National Environmental Board No. 20 (2543), dated 31 August 2543.

- Sea water Quality Standards according to the National Environmental Board No. 27 (2549), dated December 26, 2549.

8.2.5 Hygiene and Safety standards

- Hygiene and Safety standards management system according to ISO standards. 18001.

8.2.6 Waste Management.

- Eliminate the waste or unused materials according to the Ministry of Industry 2548 dated December 27, 2548.

70

8.2.7 Listening to public opinion.

- According to the Prime Minister ministry policies by listening to public opinion, 2548 dated 30 JUNE 2548.

- Ministry of Natural Resources and Environment "To establish rules, policies, procedures and guidelines for the preparation of the environmental impact assessment for projects activities that might cause serious impact on the community both quality of the environment, natural resources, and health 2552 dated December 29, 2552.

Details related to the standards of environment are shown in Appendix C.

8.3 Environmental Impact and Control

8.3.1 Air Pollutions

The controled level of air pollutions emitted from the Krabi coal power plant at full capacity (100% doad) by assessing the concentration of pollutants in the air around the project area are summarized as follows:

Type unit concentration (@ O2 = 7%, 25 C, dry).

Sulfur dioxide (SO2) ppmVd * 50 (180)

Oxides of nitrogen in the form of ppmVd * 70 (200)

Nitrogen dioxide (NO2)

Dust mg / Nm3 30 (80)

Note: * part per millions by volume, dry basis.

No. ( ) is the standard control Emission level from new power plants.

71

Air pollution during the implementation of the project is caused by burning coal. The main pollutant contaminants releasing along with exhaust are particulates ,sulfur dioxide (SO2) and nitrogen oxides (NOx), in which the project has designed to install equipment to control air quality with the details below.

1) Dust from the Burning.

In the process of burning coal will generate coal ash, fly ash, which are of fine powder and bottom ash that could drift along with exhaust and will be integrated conglomerate then fall to the bottom of the burner.

Control

- Install a device to trap dust and fly ash, an electrostatic precipitator: ESP

2) Dust from coal transportation.

The project is the source of coal dust both from unloading coal from a ship and transporting for coal storage in the coal storage building.

Control

- Using the closed system coal conveyor system along the conveyor and spray water at the end of the coal belt before getting into sprinkler filters and installing sprinkler systems in areas where dust exists at various key points to reduce the spread of coal dust.

- Building coal yard covering as well as equipped with spraying water around the coal yard area.

3) Sulfur dioxide: SO2

Formed in the combustion process since the coal contains sulfur.

Control

72

- Sulfur dioxide removal system using a wet-limestone flue gas desulphurization: FGD.

4) Nitrogen oxides (NOx).

Formed in the Nitrogen (N2) combustion, which is the main content of air with the two main factors, high-temperature combustion, and the long duration of air and fuel combustion in the area of combustion.

Control

- Installation oxides of nitrogen removal system, a Selective Catalytic Reduction (SCR).

- Use a steam generator, Supercritical Pressure Steam Generator, high efficiency of fuel combustion that can control of Nitrogen Oxides resulting from combustion to lower environmental standard level by using a Low NOx Burner and nozzle system Flue Gas Recirculation and circulating hot gas leaving the steam generator back into the combustion chamber again. This will control the temperature within the furnace to be not too high to reduce nitrogen oxides.

After such the process to control pollution, emissions will be released into the atmosphere at the stack height approximately 200 m from the ground, so the exhaust can be dispersed in the atmosphere to reduce the accumulation of emissions around the power plant. In addition, EGAT also take into account air quality during the implementation of the project with the steps bellows,

Tracking Policies

1) Installed equipment to monitor the drainage pollutant air continuous (continuous emission monitoring system; CEMs) which is a measuring tool and displaying the concentration of sulfur dioxide (SO2), oxides of nitrogen (NOx), oxygen (O2),. flow rate, and temperature of the hot gases emitted through the chimney (flue gas temperature) by CEMs equipment which will be installed in the hot gas chimney as well as arrangements for making the Manual Sampling.

73

2) Measurements of air quality in atmosphere, Continuous Ambient Air Quality Monitoring Station: AAQMS) for air quality monitoring at all times to get information on the environment and public health.

8.3.2 Noise pollutions

In the duration of construction, the project will have noise pollution from the use of construction equipments which produce sound at the sound source is in the range 75-101 dB (A). The project will provide hearing protections for construction workers and let noise pollution generated at lunch time only.

In the duration of operation, the sound sources of the project are from the operation of steam generators, steam turbines, cooling tower, water pumps and coal conveyors, etc. The noise level is estimated less than 85 dB (A) In addition there will be noise during the test.(Pre-Commissioning) before running and maintenance systems, however, there will be noise for a short period of about 3-5 minutes/time only.

Control

- Install a silencer at the blowout valve and release valve.

- Noise hood around noisy machinery or equipment.

- Noise damper in the ducts of the fans.

- Acoustic insulation around ducts / piles.

- The specification of machinery and gear noise is not more that 85 dB (A) at a distance from the sound source 1 m. and not more than 54 dB (A) at a distance from the sound source 122 m. (Ref. according to the standard noise levels from machinery used in the power plants of the American national Standards B. 133.8-1977).

74

- During running power plants if a device which is a source of noise over is 85 dB (A) this requires mapping the noise level (Noise Contour Map) to define load noise area loudly as to inform workers who are getting into the noisy areas.

- Building a machine control around combustion areas.

- Provide personal protective equipment such as ear plugs for workers or who are in a noisy area.

- Plant trees in the project area, close to the community as a sound barrier (Buffer Zone).

In addition, the project also has additional requirements that sound level that power plant employees stand should not be more than 90 dB (A) in the eighth consecutive working hours/ shifts.

8.3.3 Pollution from waste water

Effluent from the processes of the project will be taken in isolation and treatment in abandoned wells for quality control. The amount and processes for wastewater treatment project are detailed in Chapter 5, Section 5.4 , about containment and wastewater treatment. The classified wastewaters as well as guidelines control for the control from these activities are as following,

Category Management approach

1. Effluent from the wastewater treatment system Drain to combine at sedimentation pond and reused as the new in the coal handling, ash and dust system from the coal yard.

2. Waste water from the water oil separation Drain to combine at sedimentation pond and system reused as the new in the coal handling, ash

and dust system from the coal yard. 3 Effluent from amphibious pond Drain to combine at sedimentation pond and

75

reused as the new in the coal handling, ash and dust system from the coal yard.

4 Waste water from the steam generator. Drain to combine at sedimentation pond and reused as the new in the coal handling, ash and dust system from the coal yard.

5. Effluents from demineralized water system Drain to combine at sedimentation pond and reused as the new in the coal handling, ash and dust system from the coal yard.

6. Sewage from for coal yard leachate manholes. Reused in the process of taking the dust from the stone yard.

7. Waste water from the cooling system Vent to the Pa Ka Sai canal.

8.3.4 Pollution from waste

The projects waste includes gypsum, fly ash, bottom ash, by product of the sulfur dioxide, and combustion elimination process can be overcome as follows:

1) Gypsum of sulfur dioxide removal process with the quantities of 463 tons per day are transported by a conveyor belt to the gypsum storage building, awaiting transport to the gypsum disposal pond by trucks. The plans provide 2 ample storage spaces throughout the life of power plants for 30 years which are

- Gypsum disposal pond -1. By improving the existing gypsum pond at the south of the power plant to increase the storage to 1,000,000 tons. This can store gypsum of the project during the first period for about 5 years (as part of its existing power plants for 150,000 tons and 720,000 tons of the project).

- Gypsum disposal pond 2. By building a 3,600,000 tons storage pond in the north of Krabi power plant that can store the rest of gypsum for the rest of power plant life.

76

2) Fly ash from the exhaust to trap the dust with the static trap for the amount of 579 tons/day will be stored in silos to await transport to a ash storage pond by a dump truck. This provides sufficient ash retention over the life of the power plant. There are 2 storage pond that includes.

- Fly ash disposal pond -1. By building the pond with the capacity of 900,000 tons, in the southern area of the plant to store fly ash of about 5 years.

- Fly ash disposal pond 2. By the construction of the pond with approximately 4,500,000 tons in the north side of the plant, near gypsum disposal pond-2, fly ash. This can collect the remaining fly as for the lifetime of the pl