Continuous evaporator

Abstract

A continuous evaporator for a horizontal waste heat steam generator is provided. The continuous evaporator includes a first evaporator heating surface that has a number of essentially vertically arranged first steam generating tubes wherein the circulation takes place from the bottom to the top, and another second evaporator heating surface located downstream of the first evaporator heating surface on the side of the flow medium, the second evaporator heating surface including a number of other essentially vertically arranged second steam generating tubes wherein the circulation takes place from the bottom to the top is provided. In order to provide a continuous evaporator with an especially simple structure and an especially long service life, a number of second steam generator tubes have an inner profiled element.

1 - 9 . (canceled) 
     
     
         10 . A once-through evaporator for a horizontal-type waste heat steam generator, comprising:
 a first evaporator heating surface comprising a first plurality of essentially vertically disposed first steam generator tubes through which a flow medium flows from bottom to top; and   a second evaporator heating surface connected downstream of the first evaporator heating surface with respect to the flow medium direction and comprising a second plurality of essentially vertically disposed second steam generator tubes through which the flow medium flows from bottom to top,   wherein the second plurality of second steam generator tubes each include an internal profile.   
     
     
         11 . The once-through evaporator as claimed in  claim 10 , wherein the internal profile is helical-spring-shaped. 
     
     
         12 . The once-through evaporator as claimed in  claim 10 , wherein the profile geometry of the respective internal profile is selected such that a specified frictional pressure drop of the flow medium is obtained via a respective second steam generator tube. 
     
     
         13 . The once-through evaporator as claimed in  claim 10 , wherein the respective internal profile is provided as a kind of internal finning in a respective second steam generator tube. 
     
     
         14 . The once-through evaporator as claimed in  claim 10 , wherein the respective internal profile is installed as a fitted component in a respective second steam generator tube. 
     
     
         15 . The once-through evaporator as claimed in  claim 10 , wherein the plurality of second steam generator tubes is connected in series as tube rows in a heating gas direction. 
     
     
         16 . The once-through evaporator as claimed in  claim 10 , wherein the first evaporator heating surface is connected downstream of the second evaporator heating surface with respect to the heating gas direction. 
     
     
         17 . A waste heat steam generator, comprising:
 a once-through evaporator as claimed in  claim 10 .   
     
     
         18 . The waste heat steam generator as claimed in  claim 17 , wherein a gas turbine is disposed upstream of the waste heat steam generator with respect to a heating gas direction. 
     
     
         19 . The waste heat steam generator as claimed in  claim 17 , wherein the internal profile is helical-spring-shaped. 
     
     
         20 . The waste heat steam generator as claimed in  claim 17 , wherein the profile geometry of the respective internal profile is selected such that a specified frictional pressure drop of the flow medium is obtained via a respective second steam generator tube. 
     
     
         21 . The waste heat steam generator as claimed in  claim 17 , wherein the respective internal profile is provided as a kind of internal finning in a respective second steam generator tube. 
     
     
         22 . The waste heat steam generator as claimed in  claim 17 , wherein the respective internal profile is installed as a fitted component in a respective second steam generator tube. 
     
     
         23 . The waste heat steam generator as claimed in  claim 17 , wherein the plurality of second steam generator tubes is connected in series as tube rows in a heating gas direction. 
     
     
         24 . The waste heat steam generator as claimed in  claim 17 , wherein the first evaporator heating surface is connected downstream of the second evaporator heating surface with respect to the heating gas direction.