Patent ID: 7434546
Filing Date: 2008-10-14
Classification: F22B

Abstract:
1. A steam generator comprising: a vertically oriented outer shell; a plurality of heat exchange tubes for carrying a primary fluid within the interior thereof, supported within the outer shell, the primary fluid being heated under pressure by an external source; a wrapper shroud encircling the heat exchange tubes and a secondary fluid volume that when filled places a secondary fluid in contact with the heat exchange tubes in heat exchange relationship with the primary fluid while being substantially isolated from the primary fluid, the wrapper shroud being interposed between the heat exchange tubes and the outer shell and spaced from the outer shell, the wrapper shroud extending above the vertical extent of the heat exchange tubes, the space between the outer shell and the wrapper shroud defining a downcomer annulus; a lower deck plate covering the wrapper shroud and the heat exchange tubes, the lower deck plate including through holes and conduits in communication with the through holes extending vertically upward providing a fluid path from the interior of the wrapper shroud to a vapor separator positioned above the lower deck plate, the vapor separator designed to separate entrained moisture from the vapor and return the moisture to the lower deck plate; a weir surrounding and affixed to a peripheral area of the lower deck plate or sludge collector top plate and extending up above the lower deck plate in a generally vertical direction toward the vapor separator and terminating at an edge below and spaced from the vapor separator; a feedwater dispenser for communicating feedwater from a feedwater inlet and dispensing the feedwater on an upper region above the weir; and a deflector having one end attached to the shell at an elevation below the vapor separator and a distal end extending in a generally downward direction at an acute angle to the shell and above the lower deck plate, the deflector being spaced from the edge of the weir.