Sual Power Station

Pennguard® lining protects the steel chimney flues of the largest coal fired station in the Philippines, located in earthquake area

2 x 609 MW coal fired Sual Power Station is the largest of its kind in the Philippines and a major supplier of power to the region. During the lining selection for the FGD steel chimney flues, it became clear that the lining had to meet several challenges. The main points of consideration were the chemical environment in the flues, the seismic activity in the earthquake region and the adverse local climate conditions.

Strongly acidic flue gas conditions

Sual Power Station mixes the desulphurized, cool gas stream with the remaining hot, unscrubbed gas, which results in a temperature of 75-85 ˚C / 135-153 ˚F in the chimney. As a result of the mixing, most of the condensate present in the scrubbed gas stream is evaporated, but small amounts of aggressive and corrosive condensate remain. As a result of the evaporation, the sulfuric acid condensate is very concentrated and very aggressive to most materials of construction.

Pennguard® linings are based on closed-cell borosilicate glass, and have unlimited resistance against high concentrations of sulfuric acid, even at high temperatures.

Seismic challenge

Sual Power Station is located in one of the most seismically active regions in the world. As a general rule for chimneys in seismically active locations, lightweight construction materials are preferred, as these will reduce the forces on the chimney shell and foundation during an earthquake.

The Pennguard® lining in the steel chimney flues of Sual Power Station meets this requirement; the total weight of a Pennguard® lining is 11.9 kg/m2 / 2.44 lbs/sqft (using 1.5” thick Pennguard® blocks).

The excellent insulating properties of a Pennguard® lining offer additional benefits: external insulation can be omitted, which further reduces weight, and thermal stresses in the steel flues are significantly reduced.

The Pennguard® lining itself can accommodate the deflections that occur in the steel flues during an earthquake, as the adhesive has good flexibility.