Organic matter removal in boiler feed water treatment of a power plant with ozone

Abstract The purpose of this work was to test the effectiveness of ozone as a treatment to remove organic matter of the boiler feed water of a power plant. In the experiments carried out in the power plant Endesa in As Pontes (Spain), chlorine was substituted for ozone in the pre‐treatment stage. The use of ozone reduced the organic content of the boiler feed water by an average 20% compared with chlorination and by 50% when ozone was combined with hydrogen peroxide. The latter treatment achieved an organic content in the boiler feed water of less than 40 μg C/L. The ozone treatment also reduced the content of trihalomethanes in the drinking water, produced by the same plant, to values in the range of 10 μg/L and even to undetectable values when ozone was combined with hydrogen peroxide, in spite of the postchlorination applied to this stream to ensure a disinfectant capacity though the distribution system.