2 replies to this topic

[DAIALOS]

Saludos Everyone

 

In my facility we have a 3,200 BHP capacity Water tube boiler, 600 psig. We burn dual fuel, Fuel Oil #6 and Biogas (`55% methane, desulfurized).

 

Steady States fuel flows are around 1.2-1.5 gpm of fuel oil #6 and 1800 - 2000 scfm Biogas.

 

The problem we are having lately is that when we maximize the biogas utilization in the boiler (Close to the numbers mentioned above) the furnace starts to oscillate vigorously. we have not found yet a possible root cause for this and at the same time this problem have kept us from the possibility to operate this boiler and its maximum efficiency (minimum fuel oil, maximum Biogas)

 

Any help in this case would be greatly appreciated

 

Thanks in advance

Gustavo

[PingPong]

The problem we are having lately is that when .....

Lately? Does that mean the problem was not there in the past? What changed since then?

the furnace starts to oscillate vigorously

Do you mean the whole furnace structure is oscillating?

 

If I am not mistaken 3200 BHP is equivalent to 31.4 MW,

1.2 to 1.5 gpm FO6 is equivalent to 3 - 4 MW

and 1800 - 2000 scfm biogas with 55% methane is equivalent to 16 - 18 MW.

 

That does not seem to match at all.

Is the boiler running at a capacity of only 60 % or so but nevertheless oscillating?

 

And what about excess air? Do you measure percent oxygen in flue gas? If so what is it?

Maybe excess air can be reduced to avoid oscillation.

 

We can keep guessing, but It seems to me that this is a question for the companies who designed and built the furnace and the  burners.

Or did you make changes to the burners since then?

[thorium90]

The "furnace starts to oscillate"? As in literally the furnace structure is actually oscillating?

Can we clarify what is the item or parameter, that is oscillating?