Waste heat recovery and conversion system and related methods

Abstract

Various embodiments of a waste heat recovery and conversion system are disclosed. In one exemplary embodiment, the waste heat recovery system may include a heat exchanger for transferring heat from a first fluid to a second fluid and a power conversion unit configured to convert the energy transferred from the first fluid to the second fluid into usable energy. The heat exchanger may include an outer duct defining an inlet and an outlet through which the first fluid flows in and out, respectively, of the outer duct. The heat exchanger may also include an inner duct disposed inside the outer duct and defining an inner channel inside the inner duct and an outer channel between an outer surface of the inner duct and an inner surface of the outer duct. The inner duct may define an internal flow channel through which the second fluid flows to exchange heat energy with the first fluid.

1 - 13 . (canceled) 
     
     
         14 . A system for recovering waste heat from a heat source and converting the recovered waste heat into useable energy, the system comprising:
 a heat exchanger configured to transfer heat from the heat source to a working fluid;   an expander driven by the working fluid and configured to expand the working fluid;   a generator-motor coupled to the expander;   a compressor coupled to the generator-motor and configured to compress intake air;   a condenser defining a fluid reservoir of the working fluid; and   a pump disposed between the generator-motor and the compressor and configured to pump the working fluid from the fluid reservoir to the heat exchanger,   wherein the heat exchanger, the expander, the fluid reservoir, and the pump comprise a thermodynamic loop that drives the generator-motor.   
     
     
         15 . The system of  claim 14 , wherein the expander, the generator-motor, and the compressor constitute a power conversion unit for converting the heat from the working fluid into useable energy, and wherein the power conversion unit is integrated with a housing of the condenser that defines the fluid reservoir. 
     
     
         16 . The system of  claim 14 , wherein the expander, the generator-motor, the compressor, the pump, and the fluid reservoir are integrally formed inside a housing of the condenser. 
     
     
         17 . The system of  claim 14 , wherein the generator-motor is configured to switch between a generator mode to produce electrical power to a motor mode to drive the compressor. 
     
     
         18 . The system of  claim 14 , wherein the generator-motor is mechanically coupled to the expander through a shaft, and the pump is mechanically coupled to the generator-motor through the shaft. 
     
     
         19 . The system of  claim 18 , further comprising a shaft coupler configured to couple the compressor to the shaft. 
     
     
         20 . The system of  claim 19 , wherein the shaft coupler comprises a clutch system. 
     
     
         21 . The system of  claim 14 , wherein the expander, the generator-motor, the pump, and the compressor are mechanically coupled to a shaft. 
     
     
         22 . The system of  claim 14 , wherein the expander comprises a plurality of turbines. 
     
     
         23 . The system of  claim 14 , wherein the generator-motor is configured to produce electrical power when driven by the expander. 
     
     
         24 . The system of  claim 14 , wherein the generator-motor is configured to deliver torque to a shaft when operated as an electric motor. 
     
     
         25 . A system for recovering waste heat from a heat source and converting the recovered waste heat into useable energy, the system comprising:
 a heat exchanger configured to transfer heat from the heat source to a working fluid;   an expander driven by the working fluid and configured to expand the working fluid;   a generator-motor coupled to the expander;   a compressor coupled to the generator-motor and configured to compress intake air;   a condenser defining a fluid reservoir of the working fluid; and   a pump disposed between the generator-motor and the compressor and configured to pump the working fluid from the fluid reservoir to the heat exchanger,   wherein the expander, the generator-motor, the compressor, the pump, and the fluid reservoir are integrally formed inside a housing of the condenser.   
     
     
         26 . The system of  claim 25 , wherein the generator-motor is configured to switch between a generator mode to produce electrical power to a motor mode to drive the compressor. 
     
     
         27 . The system of  claim 25 , wherein the generator-motor is mechanically coupled to the expander through a shaft, and the pump is mechanically coupled to the generator-motor through the shaft. 
     
     
         28 . The system of  claim 27 , further comprising a shaft coupler configured to couple the compressor to the shaft. 
     
     
         29 . A system for recovering waste heat from a heat source and converting the recovered waste heat into useable energy, the system comprising:
 a heat exchanger configured to transfer heat from the heat source to a working fluid;   an expander driven by the working fluid and configured to expand the working fluid;   a generator-motor coupled to the expander;   a compressor coupled to the generator-motor and configured to compress intake air;   a condenser defining a fluid reservoir of the working fluid; and   a pump disposed between the generator-motor and the compressor and configured to pump the working fluid from the fluid reservoir to the heat exchanger,   wherein the expander, the generator-motor, the pump, and the compressor are mechanically coupled to a shaft.   
     
     
         30 . The system of  claim 29 , wherein the expander, the generator-motor, and the compressor constitute a power conversion unit for converting the heat from the working fluid into useable energy, and wherein the power conversion unit is integrated with a housing of the condenser that defines the fluid reservoir. 
     
     
         31 . The system of  claim 29 , wherein the generator-motor is configured to switch between a generator mode to produce electrical power to a motor mode to drive the compressor. 
     
     
         32 . The system of  claim 29 , wherein the generator-motor is configured to produce electrical power when driven by the expander. 
     
     
         33 . The system of  claim 29 , wherein the generator-motor is configured to deliver torque to a shaft when operated as an electric motor.