Abstract: A steam generator has a nitrogen removal device for fuel gas and a combustion chamber, which is followed on the fuel-gas side, via a horizontal gas flue and a vertical gas flue, by a nitrogen removal device for the fuel gas. The steam generator has a particularly low space requirement and ensures a reliable removal of nitrogen from the fuel gases of the fossil fuel. For this purpose, the combustion chamber has a number of burners arranged level with the horizontal gas flue. Moreover, the vertical gas flue is designed for substantially vertical flow of the fuel gas from the bottom upward, and the nitrogen removal device for fuel gas is designed for an substantially vertical flow of the fuel gas from the top downward.

Abstract: In plants for generating steam using waste heat, the heat in the hot waste gases flowing through the steam generator must be utilized with maximum efficiency. To this end, the feed water is branched into two streams, one of which flows into the high-pressure heating surfaces and the other into the heating surfaces of the medium-pressure evaporator. The division of the two streams is controlled as a function of the quality of the steam, so that the steam in the heating surfaces of the intermediate superheater is heated to the same temperature as the steam in the heating surfaces of the high-pressure superheater. The invention is particularly useful in combined gas and steam turbine power plants.