Municipal solid waste fuel steam generator with waterwall furnace platens

Abstract

A steam generator includes a furnace configured and adapted to generate a stream of furnace exit gases from the combustion of municipal solid waste fuel. At least one superheater is disposed within an upper portion of the furnace or backpass. The superheater is configured and adapted to superheat fluids within the superheater by facilitating heat transfer between fluids within the superheater and furnace exit gases outside the superheater. At least one waterwall furnace platen is disposed within the furnace upstream from the superheater, the waterwall furnace platen is configured and adapted to lower furnace exit gas temperature at the superheater by facilitating heat transfer between fluids within the waterwall furnace platen and furnace exit gases outside the waterwall furnace platen.

1 - 8 . (canceled) 
     
     
         9 . A waterwall furnace platen for use in a municipal solid waste fuel steam generator, the waterwall furnace platen comprising:
 a) a bank of tubes configured with membrane construction and adapted to facilitate heat transfer between a fluid circulating within the tubes and a stream of furnace exit gases passing outside the tubes, wherein the bank of tubes includes a corrosion resistant material.   
     
     
         10 . A waterwall furnace platen as recited in  claim 9 , wherein the corrosion resistant material includes an overlay disposed on an exterior surface of the bank of tubes, the overlay including an Inconel® alloy. 
     
     
         11 . A waterwall furnace platen as recited in  claim 10 , wherein the overlay includes Inconel® 625. 
     
     
         12 . A waterwall furnace platen as recited in  claim 9 , wherein the waterwall furnace platen is configured and adapted to be positioned within the furnace to allow maintenance access to the superheater. 
     
     
         13 . A waterwall furnace platen as recited in  claim 12 , wherein the waterwall furnace platen includes a header piping expansion loop configured and adapted to accommodate for thermal expansion by flexing. 
     
     
         14 - 32 . (canceled)