Heat exchanger

Abstract

A heat exchanger includes a central chamber, having a proximal end and a distal end. A return manifold is connected to the distal end of the central chamber. A plurality of tubes, are positioned around the central chamber. An exhaust manifold receives the tubes and includes an exhaust vent. The central chamber is insulated for the portion within the exhaust manifold.

We claim:  
     
         1 . A heat exchanger, comprising: 
 a) a central chamber having a proximal end and a distal end;    b) a return manifold connected to the distal end of the central chamber;    c) a first plurality of straight tubes each having a proximal end and a distal end connected to the return manifold, said first plurality of straight tubes being arranged in a first circumferential pattern around the central chamber; and    e) an exhaust manifold connected to the proximal ends of the straight tubes, said exhaust manifold having an exhaust vent; 
 wherein a portion of the central chamber passes through the exhaust manifold and further wherein the portion of the central chamber passing through the exhaust manifold is insulated in such a way as to minimize heat loss to the exhaust manifold.  
   
     
     
         2 . A heat exchanger, comprising: 
 a) a central chamber having a proximal end and a distal end;    b) a return manifold connected to the distal end of the central chamber;    c) a first plurality of straight tubes each having a proximal end and a distal end connected to the return manifold, said first plurality of straight tubes being arranged in a first circumferential pattern around the central chamber;    d) a second plurality of straight tubes each having a proximal end and a distal end connected to the return manifold, said second plurality of straight tubes being arranged in a second circumferential pattern around the central chamber; and    e) an exhaust manifold connected to the proximal ends of the straight tubes, said exhaust manifold having an exhaust vent; 
 wherein a portion of the central chamber passes through the exhaust manifold and further wherein the portion of the central chamber passing through the exhaust manifold is insulated in such a way as to minimize heat loss to the exhaust manifold.  
   
     
     
         3 . A heat exchanger as recited in  claim 2 , wherein the central chamber is a tube.  
     
     
         4 . A heat exchanger as recited in  claim 3 , wherein the straight tubes are parallel with the central chamber tube.  
     
     
         5 . A heat exchanger as recited in  claim 2 , further comprising a heat transfer fluid source.  
     
     
         6 . A heat exchanger as recited in  claim 5 , wherein the heat transfer fluid source comprises a small bore immersion burner.  
     
     
         7 . A heat exchanger as recited in  claim 2 , further comprising a flange for mounting the heat exchanger to a tank.  
     
     
         8 . A heat exchanger as recited in  claim 5 , wherein the heat transfer fluid sources comprises a heat transfer fluid.  
     
     
         9 . A heat exchanger as recited in  claim 8 , wherein the heat transfer fluid comprises steam.  
     
     
         10 . A heat exchanger as recited in  claim 8 , wherein the heat transfer fluid comprises synthetic organic fluids, silicone fluids or mixtures thereof.  
     
     
         11 . A heat exchanger as recited in  claim 2 , wherein the insulation portion of the central chamber is on the exterior of the central chamber.  
     
     
         12 . A heat exchanger as recited in  claim 2 , wherein the insulated portion of the central chamber is on the interior of the central chamber.  
     
     
         13 . A heat exchanger as recited in  claim 2 , wherein the insulated portion of the central chamber comprises a ceramic fiber blanket.  
     
     
         14 . A heat exchanger as recited in  claim 13 , wherein the insulated portion of the central chamber further comprises a stainless steel skin over the ceramic fiber blanket.  
     
     
         15 . A heat exchanger for heating a fluid in a container, the heat exchanger comprising: 
 a) a flange sealing mounted to the container;    b) a center tube having a proximal end and a distal end, said center tube being immersed in the fluid;    c) a return manifold connected to the distal end of the center tube, said return manifold being immersed in the fluid;    d) a first set of straight tubes each having a proximal end and a distal end connected to the return manifold, said first set of tubes being positioned in a circumferential pattern at a first radius around the center tube and parallel to the center tube, said first set of tubes being immersed in the fluid;    e) a second set of straight tubes each having a proximal end and a distal end connected to the return manifold, said second set of tubes being positioned in a circumferential pattern at a second radius around the center tube and parallel to the center tube, said second set of tubes being immersed in the fluid;    f) an exhaust manifold connected to the proximal ends of the first and second sets of tubes, said exhaust manifold having a vent located outside the container;    g) a heat transfer fluid source capable of producing heated fluids connected to the proximal end of the center tube; wherein a portion of the central tube passes through the exhaust manifold and further wherein the portion of the central tube passing through the exhaust manifold is insulated in such a way as to minimize heat loss to the exhaust manifold; and    h) a flowpath for heated fluids extending from the heat transfer fluid source to the distal end of the center tube, to the return manifold, to the distal ends of the first and second sets of the tubes, to the proximal ends of the first and second sets of the tubes, to the exhaust manifold, to the vent.    
     
     
         16 . A heat exchanger as recited in  claim 15 , wherein the first set of straight tubes are equally spaced relative to one another.  
     
     
         17 . A heat exchanger as recited in  claim 15 , wherein the second set of straight tubes are equally spaced relative to one another.  
     
     
         18 . A heat exchanger as recited in  claim 15 , wherein the heat transfer fluid source comprises a small bore immersion burner.  
     
     
         19 . A heat exchanger as recited in  claim 15 , wherein the central tube is insulated with a ceramic fiber blanket.  
     
     
         20 . A heat exchanger as recited in  claim 19 , further comprising a stainless steel skin over the ceramic fiber blanket.  
     
     
         21 . A heat exchanger for heating a fluid in a container, the heat exchanger comprising: 
 a) a flange sealing mounted to the container;    b) a center tube having a proximal end and a distal end, said center tube being immersed in the fluid;    c) a return manifold connected to the distal end of the center tube, said return manifold being immersed in the fluid;    d) a first set of straight tubes each having a proximal end and a distal end connected to the return manifold, said first set of tubes being positioned in a circumferential pattern at a first radius around the center tube and parallel to the center tube, said first set of tubes being immersed in the fluid;    e) a second set of straight tubes each having a proximal end and a distal end connected to the return manifold, said second set of tubes being positioned in a circumferential pattern at a second radius around the center tube and parallel to the center tube, said second set of tubes being immersed in the fluid;    f) an exhaust manifold connected to the proximal ends of the first and second sets of tubes, said exhaust manifold having a vent located outside the container;    g) a heat transfer fluid source capable of producing heated fluids connected to the proximal end of the center tube; wherein a portion of the central tube passes through the exhaust manifold;    h) an annular tube jacketing the portion of the central tube passing through the exhaust manifold; wherein the annular tube is insulated in such a way as to minimize heat loss to the exhaust manifold; and    i) a flowpath for heated fluids extending from the heat transfer fluid source to the distal end of the center tube, to the return manifold, to the distal ends of the first and second sets of the tubes, to the proximal ends of the first and second sets of the tubes, to the exhaust manifold, to the vent.