Apparatus, systems, and methods for pre-heating feedstock to a melter using melter exhaust

Abstract

Feedstock supply structure apparatus, including an exhaust conduit fluidly and mechanically connectable to a structure defining a melting chamber, the exhaust conduit positioned at an angle to vertical ranging from 0 to about 90 degrees. The exhaust conduit may include a heat exchange substructure, or the conduit itself may serve as a heat exchanger. A feedstock supply structure fluidly connected to the exhaust conduit. Systems include a structure defining a melting chamber and an exhaust conduit fluidly connected to the structure. The exhaust conduit includes a heat exchange substructure for preheating the feedstock. Methods include supplying a granular or pellet-sized feedstock to the melter exhaust conduit, the exhaust conduit including the heat exchange substructure, and preheating the feedstock by indirect or direct contact with melter exhaust in the heat exchange substructure.

What is claimed is: 
     
         1 . A system comprising (consisting essentially of, consisting of):
 (a) a structure defining a melting chamber;   (b) one or more exhaust conduits fluidly connected to the structure defining the melting chamber and comprising a heat exchange substructure, the one or more exhaust conduits positioned at an angle to vertical ranging from 0 to about 90 degrees;   (c) a feedstock supply structure fluidly connected to the one or more exhaust conduits.   
     
     
         2 . The system in accordance with  claim 1  wherein the angle ranges from about 10 to about 75 degrees. 
     
     
         3 . The system in accordance with  claim 1  wherein the angle is greater than 80 degrees, and the feedstock supply structure includes a feedstock advancing mechanism. 
     
     
         4 . The system in accordance with  claim 1  wherein the feedstock supply structure and the heat exchange substructure are configured to allow feedstock having granule or pellet size feedstock to flow into the melting chamber and allow indirect heat exchange from at least some of the exhaust flowing from the melting chamber to at least some of the feedstock. 
     
     
         5 . The system in accordance with  claim 4  wherein the size of the feedstock granules or pellets ranges from about 1 cm to about 10 cm (or from about 1-5 cm, or from about 1-2 cm). 
     
     
         6 . The system in accordance with  claim 1  wherein at least one of the one or more exhaust conduits is at an angle of 0 degrees to vertical, and the feedstock supply structure comprises;
 a horizontal feedstock supply conduit fluidly connected to the at least one of the one or more exhaust conduits above the heat exchange substructure, 
 a feedstock supply container fluidly connected to the horizontal feedstock supply conduit, and 
 a feedstock advancing mechanism disposed in the horizontal feedstock supply conduit, the feedstock advancing mechanism in turn connected to a prime mover. 
 
     
     
         7 . The system in accordance with  claim 6  wherein the heat exchange substructure comprises one or more internal structures (baffles, distributor plates, grids) for causing a tortuous flow path for the feedstock and for the exhaust. 
     
     
         8 . The system in accordance with  claim 1  wherein at least one of the one or more exhaust conduits comprises the first vertical exhaust conduit comprising the heat exchange substructure fluidly connecting the melting chamber to a first 3-way flow connector, the first 3-way flow connector fluidly connecting the first vertical exhaust conduit comprising the heat exchange substructure with a second vertical exhaust conduit and an angled exhaust conduit, the angled exhaust conduit being at an angle ranging from about 25 to about 60 degrees to vertical, the angled exhaust conduit fluidly connected to a second 3-way flow connector, the second 3-way flow connector fluidly connecting the angled exhaust conduit to a third vertical exhaust conduit and with an angled feedstock supply conduit, and the feedstock supply structure comprises:
 a feedstock supply container fluidly connected to the angled feedstock supply conduit, and 
 the first 3-way flow connector or the second vertical exhaust conduit comprising a damper mechanism disposed therein for diverting at least a portion of the exhaust to the first angled exhaust conduit, the damper mechanism in turn connected to a prime mover. 
 
     
     
         9 . The system in accordance with  claim 8  comprising an auxiliary exhaust connection between the second and third vertical exhaust conduits. 
     
     
         10 . The system in accordance with  claim 1  wherein at least one of the one or more exhaust conduits comprises an angled exhaust conduit serving as the heat exchange substructure, the angled exhaust conduit fluidly connecting the melter chamber to a 3-way flow connector, the 3-way flow connector fluidly connecting the angled exhaust conduit with an angled feedstock supply conduit and to a vertical exhaust conduit, the feedstock supply structure comprises a feedstock supply container fluidly connected to the angled feedstock supply conduit. 
     
     
         11 . The system in accordance with  claim 10  comprising a vent conduit fluidly connecting the feedstock supply container to the second vertical exhaust conduit. 
     
     
         12 . A feedstock supply structure apparatus comprising:
 (a) an exhaust conduit fluidly and mechanically connectable to a structure defining a melting chamber, the exhaust conduit positioned at an angle to vertical ranging from 0 to about 90 degrees;   (b) the exhaust conduit comprising a heat exchange substructure; and   (c) a feedstock supply structure fluidly connected to the exhaust conduit.   
     
     
         13 . The feedstock supply structure apparatus in accordance with  claim 12  wherein the exhaust conduit is at an angle of 0 degrees to vertical, and the feedstock supply structure comprises;
 a horizontal feedstock supply conduit fluidly connected to the exhaust conduit above the heat exchange substructure, 
 a feedstock supply container fluidly connected to the horizontal feedstock supply conduit, and 
 a feedstock advancing mechanism disposed in the horizontal feedstock supply conduit, the feedstock advancing mechanism in turn connected to a prime mover. 
 
     
     
         14 . A method comprising:
 (a) supplying a granular or pellet-sized feedstock to an exhaust conduit from a melter, the exhaust conduit comprising a heat exchange substructure;   (b) preheating the granular or pellet-sized feedstock by indirect contact with melter exhaust in the heat exchange substructure.   
     
     
         15 . A method comprising:
 (a) supplying a granular or pellet-sized feedstock to an exhaust conduit from a melter, the exhaust conduit comprising a heat exchange substructure;   (b) preheating the granular or pellet-sized feedstock by direct contact with melter exhaust in the heat exchange substructure.   
     
     
         16 . A method comprising:
 (a) supplying a granular or pellet-sized feedstock to an exhaust conduit from a melter, the exhaust conduit serving as a heat exchange substructure;   (b) preheating the granular or pellet-sized feedstock by direct contact with melter exhaust in the exhaust conduit.