Conversion of HFO Firing Steam/Power Plant to Gas-Efficiency Impact

[flyingscot]

I am trying to get a handle on the typical impact of changing from HFO firing to gas firing for a steam boiler plant. I have heard arguements that thermal efficiency will drop (by between 2 and 4%) as a result of increased latent heat losses in the fuel gas due to the higher hydrogen content in gas. This argument seems a little simplistic to me as a multitude of other factors may act to minimise this impact or even result in a small efficiency improvement. Does anyone have any good insights???? What is the likely impact of a fuel change on efficiency and why?

Thanks

 

[TBP]

There won't be much difference overall between these two fuels.

It'll be hard to calculate the efficiency difference between fuels for most industrial boilers, as few plants will spend the money necessary for any kind of accurate steam metering. Many plants have worn-out old orifice plates for metering steam that were likely never properly sized in the first place. A good number of those orifice plates are installed backwards anyway. Even with properly sized vortex shedding meters, proper pressure compensation is very important for accurate readings. Without accurate steam production readings, any efficiency calculations are pretty much based on somebody's "best guess".