Fluid Recirculating Economizer

Abstract

A flue gas heat recovery device is described. The device includes a packing tower. The packing tower is adapted to receive a flue gas stream. The packing tower also contains at least one water inlet, a water collection reservoir and a packing tray positioned between the inlet and reservoir. An air induction assembly may be attached to the packing tower or the inlet. A fuel gas line is in thermal communication with the reservoir. The fuel gas line has two ends a first end in close spatial relationship to a distal end of said reservoir, and a second end in close spatial relationship to a fuel output. Finally, a fluid conduit connects the second end of the fuel gas line and the water inlet.

1 . A flue gas heat recovery device comprising:
 a. a packing tower adapted to receive a flue gas stream; wherein said packing tower contains at least one water inlet, a water collection reservoir and a packing tray positioned intermediate said water inlet and said reservoir;   b. a fuel conduit in thermal communication with the reservoir, wherein the fuel conduit has a first end in close spatial relationship to a first end of said reservoir, and a second end in close spatial relationship to a fuel supply point;   c. a fluid conduit having a first end in fluid communication with an exterior surface of the fuel gas line and a second end in fluid communication with said water inlet; and   d. at least one fan connected to the packing tower.   
     
     
         2 . The flue gas heat recovery device of  claim 1  wherein said packing tower comprises a vertically-oriented cylinder. 
     
     
         3 . The flue gas heat recovery device of  claim 1  wherein said packing tower is adapted to be integrated into a stack. 
     
     
         4 . The flue gas heat recovery device of  claim 1  further comprising a recirculation pump in fluid communication with said water inlet. 
     
     
         5 . The flue gas heat recovery device of  claim 1  wherein said water inlet further comprises a nozzle. 
     
     
         6 . The flue gas heat recovery device of  claim 1  wherein said packing tower further comprises a combustion gas inlet positioned proximate to said packing tray. 
     
     
         7 . The flue gas heat recovery device of  claim 1  wherein thermal communication between the fuel gas line and the reservoir comprises a heat transfer jacket. 
     
     
         8 . The flue gas heat recovery device of  claim 7  wherein the heat transfer jacket comprises an external surface wherein said external surface is insulated and an internal chamber wherein said fuel gas line traverses the internal chamber. 
     
     
         9 . The flue gas heat recovery device of  claim 1  wherein the packing tower, the fuel line, and the fluid conduit form a closed-loop system. 
     
     
         10 . A method for recovering heat from flue effluent, the method defining a heat recovery cycle comprising:
 a. contacting the effluent with a heat transfer fluid for a time sufficient to transfer heat from the effluent to the heat transfer fluid;   b. introducing air into the effluent to decrease the temperature of the effluent and to improve combustion;   c. transferring heat from the now heated heat transfer fluid to a fuel gas so as to heat the gas and cool the heat transfer fluid;   d. combusting the now heated fuel gas which leads to the production of additional flue effluent; and.   e. returning to step (a) utilizing the now cooled heat transfer fluid and the additional flue effluent.   
     
     
         11 . The method for recovering heat from flue effluent of  claim 10 , wherein said heat transfer fluid comprises water. 
     
     
         12 . The method for recovering heat from flue effluent of  claim 10 , wherein said heat transfer fluid is exposed to sufficient effluent to reach the temperature of about 65 degrees Celsius. 
     
     
         13 . The method for recovering heat from flue effluent of  claim 10 , wherein said transferring of heat from the heated heat transfer fluid to a fuel gas occurs in a heat transfer jacket without direct physical contact of the fuel gas and the heat transfer fluid. 
     
     
         14 . The method for recovering heat from flue effluent of  claim 10 , wherein said heat transfer fluid is reused in multiple cycles. 
     
     
         15 . A method for recovering heat from flue effluent to maintain stable temperatures during pressure changes, the method defining a heat recovery cycle comprising:
 a. contacting the effluent with a heat transfer fluid for a time sufficient to transfer heat from the effluent to the heat transfer fluid;   b. introducing air to the effluent to decrease the temperature of the effluent and to improve combustion;   c. transferring heat from the now heated heat transfer fluid to a fuel gas line so as to heat the gas line and cool the heat transfer fluid;   d. combusting further fuel to produce additional effluent; and.   e. returning to step (a) utilizing the now cooled heat transfer fluid and the additional flue effluent.   
     
     
         16 . The method for recovering heat from flue effluent of  claim 15 , wherein said fuel gas line receiving heat from the heat transfer fluid is a high pressure gas line. 
     
     
         17 . The method for recovering heat from flue effluent of  claim 16  wherein said high pressure gas line contains fuel at 1200 psi. 
     
     
         18 . The method for recovering heat from flue effluent of  claim 15 , wherein said fuel gas line receiving heat from the heat transfer fluid is a low pressure gas line. 
     
     
         19 . The method for recovering heat from flue effluent of  claim 18 , wherein said low pressure gas line contains fuel at 80 psi.