Waste heat steam generator

Waste heat steam generator for the extraction of heat from hot, dust laden gases under pressure, the generation of steam from the extracted heat and the separation of dust from the dust laden gases, comprising:

• a gas feedline for conducting hot, dust laden gases under pressure inside a gas exhaust line formed by the wall of the gas feedline and an outer spaced wall around the gas feedline, a pressure vessel with a heat exchanger space concentrically arranged in the pressure vessel, a plurality of heat exchange elements disposed in the heat exchanger space, containment walls with heat exchanger tubes and open at the bottom surrounding the heat exchange space and spaced from the pressure vessel wall, said gas feedline for conducting hot, dust laden gases opening from above into the heat exchanger space for discharge therein downwardly of the hot, dust laden gases in contact with the heat exchange elements with passage of the gases through the open bottom of the containment walls and reversal of flow of the gases upward through the space between the containment walls and the pressure vessel wall, said pressure vessel wall of the upper end of the pressure vessel connected to said outer spaced wall around the gas feedline for continued discharge of the cooled exhaust gases through the gas exhaust line, a funnel-shaped pressure vessel bottom connected to the pressure vessel wall for collecting dust precipitated from the dust laden gases, and a dust removal device for removing dust connected to the funnel-shaped bottom, wherein heat exchange elements are connected as two parallel connected recirculation loops which can be regulated separately with one recirculation loop connected to evaporator heating surfaces in the heat exchanger space and the other recirculation loop connected to heat exchanger tubes of the containment walls, support tubes for the heat exchange elements and heat exchanger tubes of the gas feedline.