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.

The embodiment of the invention in which an exclusive property or privilege is claimed is defined as follows: 
     
         1 . A flue gas heat recovery device comprising:
 a packing tower adapted to receive a flue gas stream from a water heater; wherein said packing tower contains at least one water inlet proximal to the top of the tower, a hot water collection reservoir proximal to the bottom of the tower, and a packing tray positioned intermediate said water inlet and said reservoir, wherein the packing tray supports a mass of packing material;   at least one pipe jacket, wherein each pipe jacket has a first end and a second end and the first end of the at least one pipe jacket is in fluid communication with the packing tower reservoir, wherein the hot water from the reservoir flows into the at least one pipe jacket, and wherein each of the at least one pipe jacket is adapted to receive a fuel conduit; and   a recirculation pump with an inlet in fluid communication with the second end of the at least one pipe jacket and an outlet in fluid communication with the packing tower's water inlet.   
     
     
         2 . The device of  claim 1 , wherein the fuel conduit supplies fuel for the water heater. 
     
     
         3 . The device of  claim 1 , wherein the fuel conduit supplies for a separate industrial process and a second fuel conduit supplies fuel for the water heater. 
     
     
         4 . The device of  claim 1 , wherein the fuel conduit forms at least two branches after going through the pipe jacket and wherein one branch powers the water heater and another branch powers a separate industrial process. 
     
     
         5 . The device of  claim 1 , wherein the fuel conduit flows into a propane vaporizer after going through the pipe jacket. 
     
     
         6 . The device of  claim 5 , wherein the fuel conduit is carrying natural gas. 
     
     
         7 . The device of  claim 5 , wherein the propane vaporizer vaporizes propane for both the water heater and an industrial process. 
     
     
         8 . The device of  claim 5 , wherein the propane vaporizer vaporizes fuel for industrial processes other than the water heater and wherein the water heater has an independent source of fuel. 
     
     
         9 . The device of  claim 1 , wherein the at least one pipe jacket is two pipe jackets. 
     
     
         10 . The device of  claim 9 , wherein one pipe jacket receives a first fuel conduit that provides fuel to the water heater and wherein the other pipe jacket receives a second fuel conduit that provides fuel to an industrial process. 
     
     
         11 . The device of  claim 10 , wherein the first fuel conduit and the second fuel conduit carry different fuels. 
     
     
         12 . The device of  claim 11 , wherein the first fuel conduit carries natural gas and the second fuel conduit carries LP Gas. 
     
     
         13 . A system for holding and heating fluid used in hydraulic fracturing, said system comprising;
 a tank with a fluid inlet conduit and a fluid outlet conduit;   a burner in fluid communication with a fire tube, wherein the fire tube is located on the interior of the tank; and   an economizer in fluid communication with the fire tube outlet, the economizer comprising:
 a substantially vertical tower; 
 a heated gas inlet located on the lower portion of the vertical tower; 
 a fluid distributing spout located on the interior of the vertical tower; 
 a plurality of packing media suspended intermediate of the heated gas inlet and the fluid distributing spout, wherein the plurality of packing media are located on the interior of the vertical tower; and 
 a fluid reservoir in communication with the bottom of the vertical tower, wherein the fluid reservoir is below the heated gas inlet; 
   a fluid outlet port proximal to the bottom of the fluid reservoir.   
     
     
         14 . The system of  claim 13 , further comprising a heat exchanger with a first loop in which heated fluid flows form the fluid outlet port through the heat exchanger and into the fluid distributing spout and a second loop in which fluid flows from the fluid inlet conduit through the heat exchanger and into the fluid outlet conduit. 
     
     
         15 . The system of  claim 13 , further comprising
 a pipe jacket, surrounding a fluid-carrying conduit; and   a recirculating pump, wherein the heated fluid flows from the first outlet port through the pipe jacket and then through the recirculating pump to the first distributing spout, thereby heating the fluid in the conduit.   
     
     
         16 . A system for heating a process fluid, said system comprising:
 a fluid tank;   a burner in fluid communication with a first end of a conduit, wherein the conduit is adapted to receive exhaust gases from the burner and wherein the conduit runs through at least a portion of the interior of the fluid tank;   an economizer, wherein the economizer is designed to receive a second end of the conduit such that exhaust gases from the burner flow through the conduit and into the economizer and wherein the exhaust gases flow upwardly in the economizer and transfer their heat to downwardly flowing liquid within the economizer;   a heat transfer jacket, wherein the heat transfer jacket receives heated liquid from the economizer; and   a process fluid conduit, wherein at least a portion of the process fluid conduit is surrounded by the heat transfer jacket such that the hot liquid from the economizer directly contacts the process fluid conduit and warms the contents of the process fluid conduit and wherein at least a portion of the process fluid conduit runs through at least a portion of the interior of the fluid tank.   
     
     
         17 . The system of  claim 16 , wherein the process fluid conduit carries a fuel to be heated. 
     
     
         18 . The system of  claim 17 , wherein at least one fuel line splits off from the process fluid conduit at a point on the process fluid conduit after the process fluid conduit exits the fluid tank. 
     
     
         19 . The system of  claim 18 , wherein one of the at least one fuel lines supplies fuel to the burner. 
     
     
         20 . The system of  claim 16 , wherein the liquid in the economizer and the liquid in the heat transfer jacket are isolated from each other and wherein heat from the liquid in the economizer is transferred to the liquid in the heat transfer jacket in a heat exchanger.