Siàƒ¢n Green, Managing Editor
South Korea’s Doosan has now completed the 656 MW, 100 MIGD Fujairah power and desalination plant in the United Arab Emirates. The plant is the first in the Middle East, and one of the largest in the world, to use a combination of multi-stage flash and reverse osmosis desalination technologies.
In April 2004, South Korea’s Doosan produced the first few litres of potable water at the Fujairah power and desalination plant. The achievement was made just 22 months after the signing of the construction contract, thus setting a world record for the construction of such a plant, according to Doosan.
The 656 MW, 455 million litres (l) per day (100 million Imperial gallon/day ” MIGD) plant was constructed by Doosan Heavy Industries and Construction Co. Ltd. of Changwon, Korea, in order to meet rapidly rising demand for electricity and water in Al Ain and the northern emirates. Located in the emirate of Fujairah, UAE, adjacent to the existing Qidfa power plant on the Gulf of Oman, this new plant will export 500 MW of electricity to the local grid via a new 400 kV transmission line. Its water output will be pumped to Sweihan through a new 180 km dual pipeline.
Electricity demand in the northern emirates has been growing at some ten per cent per year in recent years in line with its growing economy and expanding population. In order to meet this demand, the UAE Offsets Group (UOG) in 2001 invited bids for construction of the project. UOG was instructed by His Highness President Sheikh Zayed Bin Sultan Al Nahyan to implement the project on a fast track basis.
Figure 1. Construction on the Fujairah power and desalination plant began in October 2001
UOG awarded the $802 million contract for the construction of the power and desalination plant to Doosan in June 2001. In the same month, an emiri decree issued by His Highness Sheikh Hamad bin Mohammad Al Sharqi, Supreme Council Member and Ruler of Fujairah, established the Union Water and Electricity Company (UWEC) to build, operate and manage the project. UWEC was established with a paid-up capital of AED1.5 billion ($409 million) from the Abu Dhabi government.
Doosan beat numerous international bids, including ones from France’s Sidem and Italy’s Fisia Italimpianti, to win the engineering, construction and procurement contract, and started construction in October 2001. It appointed British firm Mott MacDonald as its architect engineer. Mott MacDonald’s duties included conceptual design for the overall power island and carrying out an environmental review.
In August 2001, UOG awarded a separate, $453 million contract for the transmission element of the project to a joint venture between local firm Al Jaber Energy Services and Technip.
The $1.2 billion project has been funded by the Abu Dhabi government. In July 2002 UWEC signed a $950 million bridge facility with 13 local, regional and international banks to finance the project. The five-year facility was lead arranged by the National Bank of Abu Dhabi and included a $790 million conventional loan and a $160 million Islamic tranche.
In line with the on-going privatization of the water and power sector in Abu Dhabi, UWEC plans to privatize the project by offering a partner a stake of up to 49 per cent.
The Fujairah project is unique in the Middle East in that it uses a combination of two different desalination technologies. It will produce 284 million l/day (62.5 MIGD) of water using multi-stage flash (MSF) technology and 171 million l/day (37.5 MIGD) using reverse osmosis (RO) technology. It is also one of the largest plants in the world to use this combination of techmologies.
This hybrid desalination system is designed to provide significant operational savings by reducing fuel consumption by up to 25 per cent compared with a similar-sized plant based only on MSF technology. Other key criteria influencing the design of the desalination plant were feed water quality, product water requirements and compatibility with the cogeneration of electricity.
The water production system at the Fujairah desalination plant is comprised of five Doosan MSF units producing 57 million l/day (12.5 MIGD) each and one RO unit with a design capacity of 171 million l/day (37.5 MIGD). The RO unit was supplied by Ondeo Degremont. For drinking water supply, distillate from the MSF units and desalinated water from the RO plant are mixed in a distillate header and treated in a re-mineralization unit before passing into the potable water storage tanks. Prior to export to the water transmission line, potable water is stored in five potable water tanks, each with a capacity of 91 million l (20 million gallons).
The five MSF evaporators (MSFE) each produce 57 million l of distillate per day (12.5 MIGD) containing less than 25 parts per million (ppm) dissolved solids with a performance ratio of 8.0 kg distillate per 2326 kJ at 109à‚°C top brine temperature. These units were built at Doosan’s Changwon facility in Korea and transported to Fujairah by sea. The first of the five MSF evaporators arrived at the project site in April 2002.
Doosan was also responsible for constructing the power island, consisting of four gas turbines, two heat recovery steam generators (HRSGs) and two steam turbines in a combined cycle configuration. The output of the power plant is 656 MW, of which 120 MW is required for the desalination process and 36 MW for the transmission system. The remaining 500 MW is exported to the grid.
The four gas turbines are GE Frame 9E units (model PG9171E) fitted with diverter dampers in order to enable the plant to operate in either combined cycle or open cycle mode. They are dual fuel units which use natural gas as the primary fuel and distillate oil as the back-up fuel. The 9E gas turbine has a design output of 126 MW and is capable of achieving more than 52 per cent efficiency in combined cycle.
The 9E units at Fujairah are fitted with a dry low NOx combustion system, while water injection is used to reduce NOx emissions when firing diesel fuel. The gross output of the four units is 424 MW when using evaporative coolers at an ambient temperature of 46à‚°C and relative humidity of 40 per cent.
The four HRSG units were supplied by Doosan. They are single pressure units with a horizontal design and are equipped for supplementary firing. The two steam turbines are back pressure units supplied by Siemens.
Like the MSF evaporators, the four HRSGs were fully assembled at Doosan’s Changwon plant before being shipped to the site. This enabled Doosan to shorten the project time by 12 months as it would usually take the company 24 months for the shipping, disassemble and reassemble processes.
Civil work for the project was carried out by Six Constructions Arabian Construction Company, while switchgear was supplied by Hyundai.
In April 2003, UWEC signed a $37 million contract with Sogex Oman for the operation and maintenance of the power and desalination plant and the water transmission pipeline. The contract entails the operation and maintenance of the entire facility for a five year term. According to UOG, Sogex’s bid for the contract was 40 per cent lower than any of the other bids it received.
Al Jaber and Technip are responsible for the project’s water transmission package, which involves the construction of a 179 km dual pipeline to Sweihan, an 18 km spur to Al Dhaid in Sharjah, as well as pumping stations, water storage tanks and associated facilities. UWEC will supply water to the Federal Electricity and Water Authority (FEWA), which will distribute water to towns including Fujairah, Ajman, Umm al Quwain, Bathna, Dafta and Masafi Al Fujairah. The pipeline will have the capacity to pump 818 million l/day (180 MIGD) of water from the plant to Sweihan.
Figure 2. The project site is located in the emirate of Fujairah, 5 km south of Khor Fakkan
A 400 kV transmission line has also been constructed to evacuate electricity from the Fujairah power plant at Qidfa to the FEWA power grid. In the long term, UWEC will be able to export the power to the planned Emirates National Grid, which will also be connected to the GCC grid ” a region-wide power network which will eventually interconnect the UAE with Oman, Kuwait, Saudi Arabia, Bahrain and Qatar.
Building for the future
According to Doosan, Fujairah was due to achieve Commercial Operation Certification in June 2004. By May 31, the plant had produced 646 million l (142 million gallons) of water and 85 193 MWh of power. The production of power and water was scheduled to be gradually increased in stages until design capacity was reached.
UWEC is now expected to privatize the Fujairah plant and is already developing a second project at Qidfa. This power and desalination plant will have a capacity of up to 1000 MW and 455 million l/day (100 MIGD). UWEC received prequalification documents from 14 international, regional and local companies for the turnkey EPC contract, which was due to be awarded by mid-2004. Germany’s Fitchner is undertaking the project management consultancy contract for the project, which is expected to be commissioned in 2006.