Can anyone introduce the derating of compressor gas engine due to the fuel gas quality? How to judge that the engine needs to be derated? What are the related factors? etc. Thanks.
Interesting topic. A few years ago I was operating a field with steadily increasing CO2. I was concerned that as the BTU content of the fuel gas decreased it would be progressively harder to pull full load. I found out that this was a non-issue because the air/fuel ratio could be adjusted to provide full power down to very low BTU ratings (the example I got from Waukesha was their machines could run a full hp on land fill gas that was over 50% CO2 and other inerts). It was just a matter of getting the right jets an/or changing out the carb for a "digester carb". My field only got to 25%, but we were able to load the machines to the hp as derated for elevation (but no deration for fuel quality).
all the manufacturers have their own derating calculations. Waukesha its own, go to this page ans searc for fuel specification, you'll even see a paper on landfill gases.