Fuel Gas Composition
Fuel Gas Composition
(OP)
Hi,
The GTG is designed based on certain composition of gas. Currently we don't have monitoring device to check the gas composition entering GTG. What is the impact to GTG if there is significant changes on the gas composition?
ppm
The GTG is designed based on certain composition of gas. Currently we don't have monitoring device to check the gas composition entering GTG. What is the impact to GTG if there is significant changes on the gas composition?
ppm





RE: Fuel Gas Composition
If the fuel composition is outside the OEM spec and this results in a significant decrease in LHV, CO, smoke and (free) carbon emissions can increase due to insufficient residence time in the combustor. Burning carbon can destroy the turbine, due localised high temperatures in the turbine section.
RE: Fuel Gas Composition
RE: Fuel Gas Composition
If you have a change in the inerts (CO2, N2, etc) there will be a noticeable change in LHV, performance and NOx emissions.
RE: Fuel Gas Composition
What are you burning ?
Digester gas ? Landfill gas ? Pipeline quality natural gas ?
What is the impact of a significant change in composition ?
Well, if you dont have enough methane in your fuel and/or you run out of the range of your fuel combustion equipment, the machine will stop....
-MJC
RE: Fuel Gas Composition
If the LHV varies significantly from the original design, the consequences are as follows:
LHV > design
The unit will input too much thermal power and it may overspeed during start-up
Or, the base load FSR will be much lower than expected.
LHV < design
The unit may not reach base load and may have difficulty firing
The problem is in the Speed Ratio and control valve(s) sizing with significantly different LHV different sizes may be needed.
OEM engineering should determine whether the gas fuel nozzle need change due to Wobbe Index changes.
Base load MW and FSR% change are the most noticeable indication of gas fuel composition change, with due consideration to changes in other conditions like ambient, steam injection, inlet filter pressure drop, etc.
saludos.
a.
RE: Fuel Gas Composition
Here is a URL for an online calculator dealing with the gas turbine technical performance:
http://members.aol.com/engware/calc3.htm
Thanks,
Gordan
http://engware.i-dentity.com