AIR PLASMA SPRAYED CATALYTIC COATINGS FOR DENOX APPLICATIONS: Fid-Bau Portal

AIR PLASMA SPRAYED CATALYTIC COATINGS FOR DENOX APPLICATIONS

Moscatelli, A. / Cemuschi, F. / Notaro, M. / Capelli, S.

The selective catalytic reduction (SCR) of NO_x by ammonia is the best‐developed and most widely applied method for removing those pollutants present within the flue gases of fossil fuelled power plants and engines. Commercial catalysts are mainly composed of TiO₂, WO₃ and V₂O₅ plus other compounds without catalytic function. TiO₂ in the anatase form acts as high specific surface support material and shows the most effective dispersive capacity for the catalytically active phases (V₂O₅ and WO₃). Nowadays, the installation of SCR DeNO_x plants is usually limited to coal, oil and waste fired power plants. In fact, NO_x emissions of natural gas combined cycles are still below the threshold fixed by the law but if this threshold will be further reduced, combined cycles will have to be equipped with DeNO_X plants or with very low NO_x burners. On the other hand, to upgrade the existing plants, a retrofitting technology is required. In this perspective, a possible solution would consist in depositing a catalytic coating on heat exchange pipes in the heat recovery steam boiler of combined cycle power plants in the region where the temperatures of flue gases are within the range of operation of the catalyst. In this work, different morphologies of precursors and microstructure of coatings have been investigated and the catalytic reduction efficiency of coating has been evaluated to select the best solution. The first results of the development of air plasma sprayed catalytic coatings will be presented.