Compressor system including gear integrated screw expander

Abstract

A compressor system includes a gear box having a first drive gear, a second drive gear and a first driven gear. A prime mover is coupled to the first drive gear and is operable to input rotational power to the gear box and a compressor is coupled to the first driven gear and is operable in response to rotation of the first driven gear to produce a flow of compressed gas. A heat exchanger is positioned to receive the flow of compressed gas and a flow of fluid and is operable to cool the flow of compressed gas and heat the flow of fluid to produce a flow of heated gas. A screw expander is coupled to the second drive gear and is operable in response to the flow of heated gas to input rotational power to the gear box.

What is claimed is: 
     
         1 . A compressor system comprising:
 a gear box including a first drive gear, a second drive gear and a first driven gear;   a prime mover coupled to the first drive gear and operable to input rotational power to the gear box;   a compressor coupled to the first driven gear and operable in response to rotation of the first driven gear to produce a flow of compressed gas;   a heat exchanger positioned to receive the flow of compressed gas and a flow of fluid and operable to cool the flow of compressed gas and heat the flow of fluid to produce a flow of heated gas; and   a screw expander coupled to the second drive gear and operable in response to the flow of heated gas to input rotational power to the gear box.   
     
     
         2 . The compressor system of  claim 1 , wherein the prime mover includes an electric motor. 
     
     
         3 . The compressor system of  claim 1 , further comprising a pump operable to produce the flow of fluid. 
     
     
         4 . The compressor system of  claim 1 , further comprising a second driven gear and a second compressor coupled to the second driven gear, the second compressor operable in response to rotation of the second driven gear to receive the flow of compressed gas and produce a second flow of compressed gas. 
     
     
         5 . The compressor system of  claim 4 , further comprising a second heat exchanger positioned to receive the second flow of compressed gas and the flow of fluid and operable to cool the second flow of compressed gas and heat the flow of fluid. 
     
     
         6 . The compressor system of  claim 1 , wherein the flow of fluid includes water and the flow of heated gas includes steam. 
     
     
         7 . The compressor system of  claim 1 , further comprising a condenser positioned to receive the flow of heated gas from the screw expander and operable to cool the flow of heated gas. 
     
     
         8 . The compressor system of  claim 1 , further comprising an external heat source positioned to receive the flow of fluid and operable to heat the flow of fluid. 
     
     
         9 . A compressor system comprising:
 a prime mover directly connected to a first drive gear and operable to produce a first torque in response to operation of the prime mover;   a screw expander directly connected to a second drive gear and operable in response to a flow of heated gas to produce a second torque;   a first compressor directly connected to a first driven gear and operable in response to rotation of the first driven gear to produce a first flow of compressed gas; and   a second compressor directly connected to a second driven gear and operable in response to rotation of the second driven gear to receive the first flow of compressed gas and produce a second flow of compressed gas, wherein the first drive gear and the second drive gear cooperate to directly rotate the first driven gear and the second driven gear.   
     
     
         10 . The compressor system of  claim 9 , wherein the prime mover includes an electric motor. 
     
     
         11 . The compressor system of  claim 9 , further comprising a first heat exchanger positioned to receive the first flow of compressed gas and a second heat exchanger positioned to receive the second flow of compressed gas. 
     
     
         12 . The compressor system of  claim 11 , wherein a flow of fluid passes through the first heat exchanger and the second heat exchanger to cool the first flow of compressed gas and the second flow of compressed gas and to produce the flow of heated gas. 
     
     
         13 . The compressor system of  claim 12 , further comprising a pump operable to direct the flow of fluid to the first heat exchanger and the second heat exchanger. 
     
     
         14 . The compressor system of  claim 12 , wherein the flow of fluid includes water and the flow of heated gas includes steam. 
     
     
         15 . The compressor system of  claim 12 , further comprising a condenser positioned to receive the flow of heated gas from the screw expander and operable to cool the flow of heated gas. 
     
     
         16 . The compressor system of  claim 9 , further comprising an external heat source positioned to receive a flow of fluid and operable to heat the flow of fluid to at least partially produce the flow of heated gas. 
     
     
         17 . A compressor system comprising:
 a first compressor rotatable to produce a first flow of compressed gas;   a second compressor rotatable to receive the first flow of compressed gas and produce a second flow of compressed gas;   a first heat exchanger positioned to receive and cool the first flow of compressed gas before directing the first flow of compressed gas to the second compressor;   a second heat exchanger positioned to receive and cool the second flow of compressed gas;   a pump operable to direct a flow of fluid to the first heat exchanger and the second heat exchanger to produce a flow of heated fluid;   a prime mover operable to produce a first torque; and   an expander operable in response to the flow of heated fluid to produce a second torque, wherein the first torque and the second torque cooperate to rotate the first compressor and the second compressor.   
     
     
         18 . The compressor system of  claim 17 , wherein the prime mover includes an electric motor. 
     
     
         19 . The compressor system of  claim 17 , wherein the expander includes a screw expander. 
     
     
         20 . The compressor system of  claim 17 , further comprising a first driven gear coupled to the first compressor, a first drive gear coupled to the prime mover and a second drive gear coupled to the expander, the first driven gear, the first drive gear and the second drive gear rotatably connected to one another. 
     
     
         21 . The compressor system of  claim 20 , further comprising a second driven gear coupled to the second compressor, the second driven gear rotatably connected to the first driven gear, the first drive gear and the second drive gear. 
     
     
         22 . The compressor system of  claim 17 , further comprising a condenser positioned to receive the flow of heated gas from the expander and operable to cool the flow of heated gas. 
     
     
         23 . The compressor system of  claim 17 , further comprising an external heat source that cooperates with the first heat exchanger and the second heat exchanger to heat the flow of fluid and produce the flow of heated fluid.