Please can you explain why we shouldn't manually transfer fuel on the frame 9E gas turbine at loads less than 30MW? and not to operate mix mode at loads less than 30MW?

 

George Avorka,

This is only a limitation on SOME GE-design Frame 9E heavy duty gas turbines--not all GE-design Frame 9E heavy duty gas turbines. You (conspicuously) did not mention the type of combustion system (conventional, or DLN-I), or the types of fuels being burned by the unit(s). Both factors can play a big role in determining these operational limitations.

In general, though, the reasons are because the fuel flow-rates below this load setpoint either result in a loss of ability to control fuel, or the fuel flow-rates will result in unstable and/or incomplete combustion which can result in loss of flame trips or serious damage to combustion hardware (fuel nozzles and combustion liners, in particular).

Hope this helps!