Patent ID: 7958853

Claim:
A steam generator comprising: a pressure-tight pressure casing enclosing a volume; at least one hollow tube extending in the casing volume, the at least one hollow tube being hermetically sealed from the casing volume; a feed section and a discharge section which fluidtightly project through the pressure casing, the at least one hollow tube fluidly connected to the feed section and to the discharge section; wherein the pressure casing includes at least one opening for feed of heat flow into the volume, and at least one opening for outlet of heat flow, configured and arranged so that heat thermally interacts with the at least one hollow tube; wherein the pressure casing is drum shaped and has a longitudinal axis and a diameter perpendicular to the pressure casing longitudinal axis; wherein the pressure casing longitudinal axis is oriented horizontally, and the pressure casing along the longitudinal axis is larger than along the pressure casing diameter; wherein the at least one hollow tube is configured and arranged to provide at least two hollow tube sections which extend parallel to each other and which are stacked vertically or vertically offset above each other, and are each interconnected in pairs at an end section in a serpentine form; wherein the discharge section is arranged in the vertical direction above the feed section; and wherein the at least one opening for feed of heat flow is located in a vertically upper section of the pressure casing, such that heat flow inside the pressure casing occurs over the hollow tube sections transversely to their longitudinal extent, with a flow direction which is oriented from the top vertically downwards.