Industrial Boilers If A Gas Flame Burns Very Blue In An Industrial Boiler What Does This Indicate?

If a gas flame burns very blue in an industrial boiler what does this indicate? - industrial boilers

Tell a large size power plant steam ship or displacement. If so, please write me a good fire, a flame is bright orange, which is the total length of the combustion chamber without the back wall. The flame should be tapered rather uneven edges.
A blue flame could be a lack of combustion air. It would be easier to see, produced gas from the flu.