PREVENTING ALKALI CORROSION IN GAS TURBINES THAT UTILIZE ALTERNATE FUELS

摘要

An earlier program characterized the chemistry controlling the deposition of the alkali sulfates and chlorides in combustors. The processes are thermodynamically driven and depending on fuel constituents a formation ranking of sulfate > chloride > carbonate > hydroxide is observed. It has now been established that adding traces of either molecular molybdenum or tungsten to the hot burned gases can supersede these preferences and benign alkali polymolybdate or polytungstate bronzes are deposited instead. As a final polisher, this is a practical and inexpensive method to fully reduce the alkali corrosion effects of synfuels in gas turbines.