Abstract: A burner operating with flameless combustion, comprising a system for sucking the recycling flue gases directly from the combustion chamber by means of an ejector fed with the comburent, a heat exchange system positioned between the recycling flue gases and the comburent, a system for injecting the fuel directly into the recycling flue gases, the latter comprising or not comprising the comburent with formation of a mixture of fuel-recycling flue gases-comburent in the zone around the outlet of the comburent ejector and following introduction of the mixture into the combustion chamber.

Abstract: A steam generator comprising: water/steam tubes passing through the steam generator from the water inlet (62, 63, 64) to the superheated steam outlet (68, 69, 610), horizontally arranged in tube banks, preferably flat tube banks, perpendicularly crossed by the fumes (61), the tubes ascend along the steam generator axis from one tube bank to the other, with an oblique path so to expose the tube to the fume flow (61) in different positions at each tube bank, the tubes are divided into two or more separate branches (65, 66, 67), each branch fed by a header distinct from the others, the steam generator being once-through in pure countercurrent, vertical or horizontal, the headers (61, 69, 610) of the outlet superheated steam are grouped at direct contact in a bundle, and they are thermally insulated from the outside.