Particulate matter (PM) emitted by the combustion of liquid fuels consist of both ash and soot particles. For installations fired on heavy fuel oil, ash particles represent a substantial fraction of the PM emitted. However, when one burns distillate oil, soot accounts for more than 95% of the PM emission. There is currently a marked move towards the reduction of particles emitted by combustion installations. This includes gas turbines operated in cogeneration or in simple/combined cycle. This trend is driven namely by the EU BREF (Best Available Techniques Reference Document) and IED (Industrial Emission Directive), which recommend more stringent PM limitations for the combustion of gaseous and liquid fuels. Due to the proposed regulations GE has performed testing to evaluate the efficiency of catalysts mobilized in the form of fuel additives on soot emissions of heavy duty gas turbines (“GT”) fired on # 2 diesel oil (#2 DO) also known as gasoil.
In the framework of a collaboration between EDF and GE, a full-scale test has been performed at the Jarry Sud power plant in Guadeloupe (West Indies), involving a Frame 6B, with three types of benign oxidation catalyst additives: cerium (IV), cerium (III) and iron (III). The results of this trial proved successful with a PM abatement level up to 80% attained at full load.
The paper summarizes the preparation and execution of this field test with emphasis placed on the activity of cerium that appeared efficient at concentrations as low as a few ppm. The performances of iron and cerium are also compared.