Sulfur deposition in a gas turbine natural gas fuel control system

The precipitation of elemental sulfur in sour gas producing reservoirs containing several tenths of a percent elemental sulfur (S8) is a common phenomenon. Occurrence of sulfur deposition in natural gas systems containing significantly lower concentrations of elemental sulfur, however, is rather infrequent. This paper describes the conditions under which sulfur precipitation observed in the fuel delivery system of a gas turbine resulted from a sulfur concentration measured in the low parts per billion by volume (ppbv). Even at these low levels of concentration, the rate of deposition was enough to interfere with the operation of the gas fuel control system to the extent that the valve plugging symptoms were readily identifiable. This report on the extensive series of rig and full scale tests that led to a solution should prove helpful in dealing with similar deposit problems in natural gas systems containing very low levels of S8.