Sual power station
On northwest Luzon, 190 kilometres from the Philippine capital Manila, one of Asia’s largest private power companies has constructed a 2 x 609 MW coal fired power station. When it enters commercial operation in 1999, the Sual Power Station will be the largest of its kind in the Philippines and a major supplier of power to the region. In order to be environmentally efficient, the station is equipped with a modern flue gas desulphurisation system.
The owner and developer of Sual Power Station is Consolidated Electric Power Asia Limited (CEPA), a subsidiary of Southern Company from the United States. CEPA already operates a number of large power stations in several Asian countries, including China and the Philippines.
The Sual Power Station will fire a range of imported coals, with a varying sulfur content. In order to meet the emission standards for SO₂, up to 70 % of the flue gas will be desulphurized in a wet flue gas desulphurization (FGD) plant. Before entering the chimney, the cool, wet treated gas is mixed with the remainder of the gas stream, which is still hot. The mixed gas stream in the chimney flues has a temperature of 75-85 °C and an SO₂ content of 800 mg/Nm³. When low sulfur coal is burned, the FGD plant is bypassed and the entire gas stream is exhausted directly through the chimney. In this case, the flue gas has a temperature of 132 °C .
The chimney of the Sual Power Station was designed by Ove Arup & Partners (Arup) from London, an engineering firm with great experience in Southeast Asia. One of the main challenges for the design to meet was the strong seismic activity in the region. Furthermore, a flue lining had to be selected, which would be resistant to the wide range of temperatures and chemical loads.
Following a detailed evaluation, the designer and the customer selected a PennguardTM lining for the internal protection of the steel chimney flues. Starting from May 1998, PennguardTM linings were installed in both flues of the 220 m high chimney, with a com-bined surface area of 9.950m²