Heat exchanger for heating or cooling bulk solids

Abstract

A heat exchanger, for heating or cooling bulk solids, includes a housing including an inlet for receiving the bulk solids, an outlet for discharging the bulk solids, and a heat exchange chamber disposed between the inlet and the outlet. The heat exchanger also includes spaced apart heat transfer tubes supported within the housing, between the inlet and the outlet, and extending through the heat exchange chamber, for indirect heat exchange of a heat exchange medium in the heat exchange chamber with the bulk solids that flow, by gravity, from the inlet, and through the heat transfer tubes, toward the outlet. The heat transfer tubes include a first end for receiving the bulk solids, and a second end for release of bulk solids. At least one of the first end and the second end is moveable relative to the housing to accommodate thermal expansion or contraction.

1 . A heat exchanger for heating or cooling bulk solids,
 the heat exchanger comprising:   a housing including an inlet for receiving the bulk solids into the housing, an outlet for discharging the bulk solids from the housing, and a heat exchange chamber disposed between the inlet and the outlet; and   a plurality of spaced apart heat transfer tubes supported within the housing, between the inlet and the outlet, and extending through the heat exchange chamber, for indirect heat exchange of a heat exchange medium in the heat exchange chamber with the bulk solids that flow, by gravity, from the inlet, and through the heat transfer tubes, toward the outlet,   the heat transfer tubes including a first end for receiving the bulk solids into the heat transfer tubes, and a second end for release of the bulk solids flowing by the force of gravity, out of the heat transfer tubes, the second end of the heat transfer tubes coupled to respective tube bellows which are coupled to the bottom plate, and the second end of the heat transfer tubes extending below the bottom plate, through the tube bellows,   
       wherein the second end is moveable relative to the housing to accommodate thermal expansion or contraction. 
     
     
         2 . The heat exchanger according to  claim 1 , wherein the first end is isolated from the heat exchange chamber and the second end is isolated from the heat exchange chamber such that the bulk solids are atmospherically isolated from the heat exchange medium in the heat exchange chamber. 
     
     
         3 . The heat exchanger according to  claim 1 , wherein the housing includes a top plate and a bottom plate enclosing the heat exchange chamber within the housing. 
     
     
         4 . The heat exchanger according to  claim 3 , wherein the heat transfer tubes are supported by the top plate. 
     
     
         5 . The heat exchanger according to  claim 4  wherein the top plate is shaped to facilitate flow of the bulk solids into the heat exchange tubes. 
     
     
         6 . The heat exchanger according to  claim 4 , wherein the heat transfer tubes are welded to the top plate. 
     
     
         7 . The heat exchanger according to  claim 4 , wherein the heat transfer tubes are supported by the bottom plate. 
     
     
         8 - 9 . (canceled) 
     
     
         10 . The heat exchanger according to  claim 1 , wherein a first end of each of the tube bellows is coupled to the bottom plate and a second end of each of the tube bellows is coupled to the second end of the respective one of the heat transfer tubes such that the heat transfer tubes extend through the tube bellows. 
     
     
         11 . The heat exchanger according to  claim 4 , wherein the heat transfer tubes extend through respective apertures in the bottom plate. 
     
     
         12 . The heat exchanger according to  claim 11 , wherein the apertures are larger than the heat transfer tubes to provide a clearance fit. 
     
     
         13 . The heat exchanger according to  claim 1 , wherein the heat exchange medium comprises a gas and the heat exchange chamber includes a gas inlet and a gas outlet for the flow of the gas through the heat exchange chamber. 
     
     
         14 . The heat exchanger according to  claim 13 , comprising baffles extending into the heat exchange chamber to facilitate circuitous flow of the gas through the heat exchange chamber. 
     
     
         15 . The heat exchanger according to  claim 1 , wherein the heat exchange tubes extend generally linearly vertically within the housing.